Battery module with phase change material

ABSTRACT

In an embodiment, a system includes a battery module, a battery cell assembly that is a component of the battery module, and a battery cell of the battery cell assembly, wherein the battery cell is configured to generate heat during operation. The battery cell assembly also includes a phase change material (PCM) disposed along a thermal pathway within the battery cell assembly that transfers the heat generated by the battery cell away from the battery cell during operation. The PCM is configured to conduct a first portion of the heat generated by the battery cell during operation. Further, the PCM is configured to absorb a second portion of the heat generated by the battery cell to affect a phase change within at least a portion of the PCM.

BACKGROUND

The present disclosure relates generally to the field of batteries andbattery modules. More specifically, the present disclosure relates tobattery cells that may be used in vehicular contexts, as well as otherenergy storage/expending applications.

This section is intended to introduce the reader to various aspects ofart that may be related to various aspects of the present disclosure,which are described and/or claimed below. This discussion is believed tobe helpful in providing the reader with background information tofacilitate a better understanding of the various aspects of the presentdisclosure. Accordingly, it should be understood that these statementsare to be read in this light, and not as admissions of prior art.

A vehicle that uses one or more battery systems for providing all or aportion of the motive power for the vehicle can be referred to as anxEV, where the term “xEV” is defined herein to include all of thefollowing vehicles, or any variations or combinations thereof, that useelectric power for all or a portion of their vehicular motive force. Aswill be appreciated by those skilled in the art, hybrid electricvehicles (HEVs) combine an internal combustion engine propulsion systemand a battery-powered electric propulsion system, such as 48 volt or 130volt systems. The term HEV may include any variation of a hybridelectric vehicle. For example, full hybrid systems (FHEVs) may providemotive and other electrical power to the vehicle using one or moreelectric motors, using only an internal combustion engine, or usingboth. In contrast, mild hybrid systems (MHEVs) disable the internalcombustion engine when the vehicle is idling and utilize a batterysystem to continue powering the air conditioning unit, radio, or otherelectronics, as well as to restart the engine when propulsion isdesired. The mild hybrid system may also apply some level of powerassist, during acceleration for example, to supplement the internalcombustion engine. Mild hybrids are typically 96V to 130V and recoverbraking energy through a belt or crank integrated starter generator.Further, a micro-hybrid electric vehicle (mHEV) also uses a “Stop-Start”system similar to the mild hybrids, but the micro-hybrid systems of amHEV may or may not supply power assist to the internal combustionengine and operates at a voltage below 60V. For the purposes of thepresent discussion, it should be noted that mHEVs typically do nottechnically use electric power provided directly to the crankshaft ortransmission for any portion of the motive force of the vehicle, but anmHEV may still be considered as an xEV since it does use electric powerto supplement a vehicle's power needs when the vehicle is idling withinternal combustion engine disabled and recovers braking energy throughan integrated starter generator. In addition, a plug-in electric vehicle(PEV) is any vehicle that can be charged from an external source ofelectricity, such as wall sockets, and the energy stored in therechargeable battery packs drives or contributes to drive the wheels.PEVs are a subcategory of electric vehicles that include all-electric orbattery electric vehicles (BEVs), plug-in hybrid electric vehicles(PHEVs), and electric vehicle conversions of hybrid electric vehiclesand conventional internal combustion engine vehicles.

xEVs as described above may provide a number of advantages as comparedto more traditional gas-powered vehicles using only internal combustionengines and traditional electrical systems, which are typically 12 voltsystems powered by a lead acid battery. For example, xEVs may producefewer undesirable emission products and may exhibit greater fuelefficiency as compared to traditional internal combustion vehicles and,in some cases, such xEVs may eliminate the use of gasoline entirely, asis the case of certain types of PHEVs.

As xEV technology continues to evolve, there is a need to provideimproved power sources (e.g., battery systems or modules) for suchvehicles. For example, it is desirable to increase the distance thatsuch vehicles may travel without the need to recharge the batteries.Additionally, it may also be desirable to improve the performance ofsuch batteries and to reduce the cost associated with the batterysystems.

SUMMARY

Certain embodiments commensurate in scope with the originally claimedsubject matter are summarized below. These embodiments are not intendedto limit the scope of the disclosure, but rather these embodiments areintended only to provide a brief summary of certain disclosedembodiments. Indeed, the present disclosure may encompass a variety offorms that may be similar to or different from the embodiments set forthbelow.

The present disclosure relates to batteries and battery modules. Morespecifically, the present disclosure relates to all electrochemical andelectrostatic energy storage technologies (e.g. ultracapacitors,nickel-zinc batteries, nickel-metal hydride batteries, and lithiumbatteries). Particular embodiments are directed to lithium ion batterycells that may be used in vehicular contexts (e.g., xEVs) as well asother energy storage/expending applications (e.g., energy storage for anelectrical grid).

In an embodiment, a system includes a battery module, a battery cellassembly that is a component of the battery module, and a battery cellof the battery cell assembly, wherein the battery cell is configured togenerate heat during operation. The battery cell assembly also includesa phase change material (PCM) disposed along a thermal pathway withinthe battery cell assembly that transfers the heat generated by thebattery cell away from the battery cell during operation. The PCM isconfigured to conduct a first portion of the heat generated by thebattery cell during operation. Further, the PCM is configured to absorba second portion of the heat generated by the battery cell to affect aphase change within at least a portion of the PCM.

In another embodiment, a method of manufacturing a battery moduleincludes disposing a phase change material (PCM) layer in a stackedorientation with respect to a substantially planar pouch battery cellthat generates heat during operation. The PCM layer includes a phasechange material (PCM) disposed between a first polymer layer and asecond polymer layer, wherein the PCM is configured to conduct a firstportion of the heat predominantly along at least one direction. Further,at least a portion of the PCM is configured to undergo a phase change byabsorbing at least a second portion of the heat at or above a phasechange temperature of the PCM.

In another embodiment, a battery module includes a battery cell assemblyhaving a pouch battery cell that generates heat during operation,wherein the pouch battery cell comprises a substantially planar surface.The battery cell assembly also includes a thermal gap pad disposedadjacent to the substantially planar surface of the pouch battery celland a phase change material (PCM) layer disposed adjacent to the thermalgap pad. The PCM layer is configured to conduct the heat predominantlyalong one direction that is perpendicular to the planar surface of thepouch battery cell. Further, the PCM layer is configured to absorb theheat to drive a phase change within at least a portion of the PCM layer.

In another embodiment, a phase change material (PCM) layer includes aphase change material (PCM) disposed within a packaging, wherein the PCMlayer is substantially planar. Additionally, the PCM layer is configuredto primarily conduct heat across the PCM layer along an axis that issubstantially perpendicular to the plane of the PCM layer over a firsttemperature range. Further, the PCM layer is configured to absorb heatover a second temperature range.

DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a perspective view of a vehicle (an xEV) having a batterysystem contributing all or a portion of the power for the vehicle, inaccordance with an embodiment of the present approach;

FIG. 2 is a cutaway schematic view of the xEV embodiment of FIG. 1 inthe form of a hybrid electric vehicle (HEV), in accordance with anembodiment of the present approach;

FIG. 3 is a cutaway schematic view of an embodiment of the xEV of FIG. 1in the form of a microhybrid electric vehicle (mHEV), in accordance withan embodiment of the present approach;

FIG. 4 is a schematic view of the mHEV embodiment of FIG. 3 illustratingpower distribution throughout the mHEV, in accordance with an embodimentof the present approach;

FIG. 5A is a front top perspective view of a battery module, inaccordance with an embodiment of the present approach;

FIG. 5B is a first side view of the battery module of FIG. 5A, inaccordance with an embodiment of the present approach;

FIG. 5C is a second side view of the battery module of FIG. 5A, inaccordance with an embodiment of the present approach;

FIG. 5D is a top view of the battery module of FIG. 5A, in accordancewith an embodiment of the present approach;

FIG. 5E is a bottom view of the battery module of FIG. 5A, in accordancewith an embodiment of the present approach;

FIG. 5F is a back view of the battery module of FIG. 5A, in accordancewith an embodiment of the present approach;

FIG. 5G is a front view of the battery module of FIG. 5A, in accordancewith an embodiment of the present approach;

FIG. 6 is an end exploded perspective view of the battery moduleembodiment of FIGS. 5A-G, in accordance with an embodiment of thepresent approach;

FIG. 7 is another exploded view of the battery module embodiment ofFIGS. 5A-G, in accordance with an embodiment of the present approach;

FIG. 8 is perspective view of a passively-cooled heat sink side plate ofa battery module, in accordance with an embodiment of the presentapproach;

FIG. 9 is perspective view of an actively-cooled heat sink side plate ofa battery module that includes one or more fans, in accordance with anembodiment of the present approach;

FIG. 10 is perspective view of an actively-cooled heat sink side plateof a battery module having a liquid cooling block, in accordance with anembodiment of the present approach;

FIG. 11 is a cross-sectional view of the battery module embodiment ofFIG. 5A taken along line 11-11, in accordance with an embodiment of thepresent approach;

FIG. 12 is a exploded schematic of a battery cell assembly of a batterymodule, in accordance with an embodiment of the present approach;

FIG. 13 is a diagram illustrating thermal dissipation pathways of abattery module, in accordance with an embodiment of the presentapproach;

FIG. 14 is a schematic of a phase change material (PCM) of a batterycell assembly of a battery module, in accordance with an embodiment ofthe present approach;

FIG. 15 is a cross-sectional schematic of a battery cell of a batterymodule taken along line 15-15 of FIG. 12, illustrated along with two PCMlayers disposed on opposite sides of the battery cell, in accordancewith an embodiment of the present approach;

FIG. 16 is a exploded schematic of a battery cell of the battery module,wherein components of the battery cell are configured to assemble toinclude an integrated internal heat fin, in accordance with anembodiment of the present approach;

FIG. 17 is a cross-sectional schematic of a battery cell embodiment ofFIG. 16 taken along line 17-17, wherein the components are assembledsuch that a frame is positioned outside of battery cell packaging thatincludes an integral internal heat fin, in accordance with an embodimentof the present approach;

FIG. 18 is a cross-sectional schematic of a battery cell embodiment ofFIG. 16 taken along line 17-17, wherein the components are assembledsuch that the frame is integrated with the battery cell packaging thatincludes the integral internal heat fin, in accordance with anembodiment of the present approach;

FIG. 19 is a perspective view of a battery module incorporating cellcasings in a stacked arrangement or orientation, in accordance with anembodiment of the present approach;

FIG. 20 is a perspective view of the battery module of FIG. 19 includinga housing configured for active cooling, in accordance with anembodiment of the present approach;

FIG. 21 is a perspective view of a closed cell casing including aplurality of integral standoffs disposed on an upper side of the cellcasing, in accordance with an embodiment of the present approach;

FIG. 22 is a perspective view of a closed cell casing including a groovedisposed in an upper side of the cell casing and configured to guidefluid flow across the upper side, in accordance with an embodiment ofthe present approach;

FIG. 23 is a schematic cross-sectional view of interlocking standoffs onadjacent cell casings, in accordance with an embodiment of the presentapproach; and

FIG. 24 is a schematic perspective view of a battery cell being disposedin a cell casing that is in an open configuration and includes a hingeabout which upper and lower sides of the cell casing rotate duringopening and closing of the cell casing, in accordance with an embodimentof the present approach;

FIG. 25 is a schematic exploded view of a battery cell having a frame,active material, an upper layer of pouch material, and a lower layer ofpouch material in accordance with an embodiment of the present approach;

FIG. 26 is a partial cross-sectional view of a battery cell whereinupper and lower pouch material layers are sealed about a frame andactive material via sealed engagement of the upper and lower materiallayers with the frame in accordance with an embodiment of the presentapproach;

FIG. 27 is a partial cross-sectional view of a battery cell whereinpouch material layers are sealed together about a frame and activematerial in accordance with an embodiment of the present approach;

FIG. 28 is a partial cross-sectional view of a battery cell whereinupper and lower pouch material layers are sealed about a frame andactive material using a grooved seal arrangement wherein the upper andlower layers are sealed together within boundaries of the frame and alsowith the frame in accordance with an embodiment of the present approach;

FIG. 29 is a partial cross-sectional view of a battery cell whereinupper and lower pouch material layers are sealed about a frame andactive material using a grooved seal arrangement wherein the upper andlower layers are sealed together within boundaries of the frame and alsowith the frame in accordance with an embodiment of the present approach;

FIG. 30 is a partial cross-sectional view of a battery cell whereinupper and lower pouch material layers are sealed about a frame andactive material using a grooved seal arrangement wherein the upper andlower layers are sealed together within boundaries of the frame and alsowith the frame in accordance with an embodiment of the present approach;

FIG. 31 is a partial cross-sectional view of a battery cell including aframe wherein upper and lower layers of pouch material are sealed insidethe frame in accordance with an embodiment of the present approach;

FIG. 32 is a schematic representation of a tool configured to facilitatesealing the layers of pouch material together as illustrated in FIGS.28-31 in accordance with an embodiment of the present approach;

FIG. 33 is a partially exploded cross-sectional side view of upper andlower layers of pouch material sealed about a frame and active materialwherein an electrode tab extends beyond the frame in accordance with anembodiment of the present approach;

FIG. 34 is a schematic of a frame having grooves configured to receiveelectrode tabs in accordance with an embodiment of the present approach;

FIG. 35 is a schematic of a frame having openings configured to receiveelectrode tabs in accordance with an embodiment of the present approach;

FIG. 36 is a schematic of a frame having openings configured to receivethe electrode tabs and a center support feature in accordance with anembodiment of the present approach;

FIG. 37 is a schematic representation of a sheet of frame sectionsarranged for assembly of multiple battery cells via a method ofmanufacturing in accordance with an embodiment of the present approach;

FIG. 38 is a block diagram of a method of assembling one or more batterycells in accordance with an embodiment of the present approach;

FIG. 39 is a schematic representation of a battery cell includingfeatures configured to facilitate filling and degassing the battery cellin accordance with an embodiment of the present approach;

FIG. 39A is a partial cross-section taken of the battery cell of FIG. 39taken along line 39A-39A in accordance with an embodiment of the presentapproach;

FIG. 40 is a schematic cross-sectional view of the battery moduleembodiment of FIGS. 5A-G, taken along the Z axis of the battery module,in accordance with an embodiment of the present approach;

FIG. 41 is an exploded perspective view of a battery cell interconnectassembly of the battery module embodiment of FIGS. 5A-G, in accordancewith an embodiment of the present approach;

FIG. 42 is a perspective view of a clamp of the battery cellinterconnect assembly embodiment of FIG. 41, in accordance with anembodiment of the present approach;

FIG. 43 is a schematic cross-sectional view of certain components of thebattery cell interconnect assembly embodiment of FIG. 41, in accordancewith an embodiment of the present approach;

FIG. 44 is a schematic cross-sectional view of a clamp being positionedover a structure of the battery cell interconnect assembly embodiment ofFIG. 41, in accordance with an embodiment of the present approach;

FIG. 45 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a hollow bar and a complementaryclamp, in accordance with an embodiment of the present approach;

FIG. 46 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a clamp structure and a clamp,in accordance with an embodiment of the present approach;

FIG. 47 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a crimping element, inaccordance with an embodiment of the present approach;

FIG. 48 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a high-voltage tape crimpingelement;

FIG. 49 is a perspective sectional view of a battery cell interconnectassembly embodiment having a single-piece spring crimping element, inaccordance with an embodiment of the present approach;

FIG. 50 is a schematic cross-sectional view of the battery cellinterconnect assembly embodiment of FIG. 49, in accordance with anembodiment of the present approach;

FIG. 51 is a schematic cross-sectional view of the battery cellinterconnect assembly embodiment of FIG. 49, showing a removal of thecrimping element using a tool in accordance with an embodiment of thepresent approach;

FIG. 52 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a clip to hold battery cell tabelectrodes together, in accordance with an embodiment of the presentapproach;

FIG. 53 is a perspective sectional view of a battery cell interconnectassembly embodiment having a roller housing structure and complementaryroller, in accordance with an embodiment of the present approach;

FIG. 54 is a schematic cross-sectional view of the roller beingpositioned in the roller housing structure of the battery cellinterconnect assembly embodiment of FIG. 53, in accordance with anembodiment of the present approach;

FIG. 55 is a schematic cross-sectional view of the roller housingstructure of FIG. 53 with the tab electrodes extending from within anopening of the roller housing structure to an outer portion of theroller housing structure, in accordance with an embodiment of thepresent approach;

FIG. 56 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a roller housing structure and ahollow roller, in accordance with an embodiment of the present approach;

FIG. 57 is a schematic cross-sectional view of a battery cellinterconnect assembly embodiment having a roller housing structure and aroller with teeth, in accordance with an embodiment of the presentapproach;

FIG. 58 is a perspective view of a portion of a first side of the cellinterconnect board of the battery module in FIG. 7, in accordance withan embodiment of the present approach;

FIG. 59 is a perspective view of a second side of the cell interconnectboard of the battery module as shown in FIG. 58, in accordance with anembodiment of the present approach;

FIG. 60 is a front view of an alternative embodiment of a battery celltab and of the cell interconnect board of FIG. 7, in accordance with anembodiment of the present approach;

FIG. 61 is a front view of a first side of the cell interconnect boardof FIG. 7, in accordance with an embodiment of the present approach;

FIG. 62 is a front view of a first side of the cell interconnect boardof FIG. 7, in accordance with an embodiment of the present approach;

FIG. 63 is a block diagram of a three-terminal battery module, inaccordance with one embodiment of the present approach;

FIG. 64 is a block diagram of a three-terminal battery module, inaccordance with another embodiment of the present approach;

FIG. 65 is a schematic of the three-terminal battery module of FIG. 64,in accordance with an embodiment of the present approach;

FIG. 66 is a front view of a cell interconnect board of thethree-terminal battery module of FIG. 65, in accordance with anembodiment of the present approach;

FIG. 67 is a front view of another cell interconnect board of thethree-terminal battery module of FIG. 65, in accordance with anembodiment of the present approach;

FIG. 68 is a block diagram of a four-terminal battery module, inaccordance with one embodiment of the present approach;

FIG. 69 is a partially exploded perspective view of the four-terminalbattery module of FIG. 68, in accordance with one embodiment of thepresent approach;

FIG. 70 is a partially exploded perspective view of the four-terminalbattery module of FIG. 68, in accordance with another embodiment of thepresent approach;

FIG. 71 is a block diagram of a four-terminal battery module, inaccordance with another embodiment of the present approach;

FIG. 72 is a partially exploded perspective view of a battery cellassembly of a battery module, in accordance with an embodiment of thepresent approach;

FIG. 73 is a perspective view of a portion of the battery cell assemblyof FIG. 72, in accordance with an embodiment of the present approach;

FIG. 74 is a top view of a portion of the battery cell assembly of FIG.73, in accordance with an embodiment of the present approach;

FIG. 75 is a bottom view of a portion of the battery cell assembly ofFIG. 72, in accordance with an embodiment of the present approach;

FIG. 76 is a cross-sectional view of a stack of the battery cellassemblies of FIG. 72, in accordance with an embodiment of the presentapproach;

FIG. 77 is a partially exploded front view of an alternative embodimentof a battery cell assembly of a battery module, in accordance with anembodiment of the present approach;

FIG. 78A is a perspective view of a portion of a battery cell assemblyof a battery module, in accordance with an embodiment of the presentapproach;

FIG. 78B is a perspective view of another portion of the battery cellassembly of FIG. 78A, in accordance with an embodiment of the presentapproach;

FIG. 79 is a cross-sectional view of a stack of the battery cellassemblies of FIG. 78A, in accordance with an embodiment of the presentapproach;

FIG. 80 is a perspective view of a cell interconnect board that couplesto the battery cell assembly of FIG. 78A, in accordance with anembodiment of the present approach;

FIG. 81 is a process flow diagram of an embodiment of a general methodfor remanufacturing a used battery module, in accordance with anembodiment of the present approach;

FIG. 82 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which a compressed andinterconnected power assembly of the used battery module isremanufactured or replaced, in accordance with an embodiment of thepresent approach;

FIG. 83 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which a cover, a side assembly,an end assembly, or a battery control assembly of the used batterymodule is remanufactured or replaced, in accordance with an embodimentof the present approach;

FIG. 84 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which a power assembly of theused battery module is remanufactured or replaced, in accordance with anembodiment of the present approach;

FIG. 85 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which an interconnect assemblyand/or top and bottom compression plates of the used battery module areremanufactured or replaced, in accordance with an embodiment of thepresent approach;

FIG. 86 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which one or more battery cellassemblies of the used battery module are remanufactured or replaced, inaccordance with an embodiment of the present approach;

FIG. 87 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which one or more layers of oneor more battery cell assemblies of the used battery module areremanufactured or replaced, in accordance with an embodiment of thepresent approach;

FIG. 88 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which an interconnect assemblyof the used battery module is remanufactured, in accordance with anembodiment of the present approach;

FIG. 89 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which thermal control featuresof the used battery module are remanufactured, in accordance with anembodiment of the present approach;

FIG. 90 is a process flow diagram of an embodiment of a method forremanufacturing a used battery module in which the interconnect assemblyis remanufactured in a manner that repurposes the battery module, inaccordance with an embodiment of the present approach; and

FIG. 91 is a schematic side view of an embodiment of a battery module inwhich sets including battery cells connected in series are connected inparallel.

DETAILED DESCRIPTION

It should be noted that terms such as “above”, “below”, “on top of”, and“beneath” may be used to indicate relative positions for elements (e.g.,stacked components of the power and battery assemblies described below)and are not limiting embodiments to either of a horizontal or verticalstack orientation. Further, should be noted that terms such as “above”,“below”, “proximate”, or “near” are intended to indicate the relativepositions of two layers in the stack that may or may not be in directcontact with one another. Additionally, geometric references are notintended to be strictly limiting. For example, use of the term“perpendicular” does not require an exact right angle, but defines arelationship that is substantially perpendicular, as would be understoodby one of ordinary skill in the art. Similarly, for example, the term“parallel” used in reference to geometric relationships does not requirea perfect mathematical relationship but indicates that certain featuresare generally extending in the same directions. Additionally, the term“planar” is used to describe features that are substantially flat, butdoes not require perfect mathematical planarity.

As discussed above, there are several different types of xEVs. Althoughsome vehicle manufacturers, such as Tesla, produce only xEVs and, thus,can design the vehicle from scratch as an xEV, most vehiclemanufacturers produce primarily traditional internal combustionvehicles. Thus, when one of these manufacturers also desires to producean xEV, it often utilizes one of its traditional vehicle platforms as astarting point. As can be appreciated, when a vehicle has been initiallydesigned to use a traditional electrical system powered by a single leadacid battery and to utilize only an internal combustion engine formotive power, converting such a vehicle into its HEV version can posemany packaging problems. For example, a FHEV uses not only thesetraditional components, but one or more electric motors must be addedalong with other associated components. As another example, a mHEV alsouses not only these traditional components, but a higher voltage battery(e.g., a 48V lithium ion battery module) must be placed in the vehiclein addition to the 12V lead acid battery along with other componentssuch as a belt integrated starter-generator, sometimes referred to as abelt alternator starter (BAS) as described in further detail below.Hence, if a battery system can be designed to reduce such packagingproblems, it would make the conversion of a traditional vehicle platforminto an xEV less costly and more efficient.

The battery systems described herein may be used to provide power to anumber of different types of xEVs as well as other energy storageapplications (e.g., electrical grid power storage systems). Such batterysystems may include one or more battery modules, each battery modulehaving a number of battery cells (e.g., lithium ion electrochemicalcells) arranged to provide particular voltages and/or currents useful topower, for example, one or more components of an xEV. Presentlydisclosed embodiments include lithium ion battery modules that arecapable of providing more than one voltage. In particular, certaindisclosed battery systems may provide a first voltage (e.g., 12V), forexample, to power ignition of a combustion engine using a traditionalstarter motor and/or support conventional 12V accessory loads, and mayprovide a second voltage (e.g., 48V), for example, to power a BAS and topower one or more vehicle accessories when the combustion engine is notrunning, for use in a microhybrid system for example. Indeed, in certainembodiments, not only may a single battery system provide two voltages(e.g., 12V and 48V), but it can provide them from a package having aform factor equivalent to a traditional lead acid 12V battery, thusmaking packaging and conversion of a traditional vehicle to a mHEVsimpler, less costly and more efficient.

Present embodiments also include physical battery module features,assembly components, manufacturing and assembling techniques, and soforth, that facilitate providing disclosed battery modules and systemsthat have a desired form factor (e.g., dimensions corresponding to atraditional lead acid battery). Further, as set forth in detail below,the disclosed battery module embodiments include a number of heattransfer devices (e.g., heat sinks, liquid-cooling blocks, heat transferfoams, phase change materials (PCMs), and so forth) that may be used topassively or actively maintain one or more temperatures of the batterymodule during operation.

With the foregoing in mind, FIG. 1 is a perspective view of an xEV 10 inthe form of an automobile (e.g., a car) having a battery system 20 inaccordance with present embodiments for providing all or a portion ofthe power (e.g., electrical power and/or motive power) for the vehicle10, as described above. Although the xEV 10 may be any of the types ofxEVs described above, by specific example, the xEV 10 may be a mHEV,including an internal combustion engine equipped with a microhybridsystem which includes a start-stop system that may utilize the batterysystem 20 to power at least one or more accessories (e.g., AC, lights,consoles, etc.), as well as the ignition of the internal combustionengine, during start-stop cycles.

Further, although the xEV 10 is illustrated as a car in FIG. 1, the typeof vehicle may differ in other embodiments, all of which are intended tofall within the scope of the present disclosure. For example, the xEV 10may be representative of a vehicle including a truck, bus, industrialvehicle, motorcycle, recreational vehicle, boat, or any other type ofvehicle that may benefit from the use of electric power. Additionally,while the battery system 20 is illustrated in FIG. 1 as being positionedin the trunk or rear of the vehicle, according to other embodiments, thelocation of the battery system 20 may differ. For example, the positionof the battery system 20 may be selected based on the available spacewithin a vehicle, the desired weight balance of the vehicle, thelocation of other components used with the battery system 20 (e.g.,battery management systems, vents or cooling devices, etc.), and avariety of other considerations.

FIG. 2 illustrates a cutaway schematic view of an embodiment of the xEV10 of FIG. 1, provided in the form of an HEV having the battery system20, which includes one or more battery modules 22. In particular, thebattery system 20 illustrated in FIG. 2 is disposed toward the rear ofthe vehicle 10 proximate a fuel tank 12. In other embodiments, thebattery system 20 may be provided immediately adjacent the fuel tank 12,provided in a separate compartment in the rear of the vehicle 10 (e.g.,a trunk), or provided in another suitable location in the xEV 10.Further, as illustrated in FIG. 2, an internal combustion engine 14 maybe provided for times when the xEV 10 utilizes gasoline power to propelthe vehicle 10. The vehicle 10 also includes an electric motor 16, apower split device 17, and a generator 18 as part of the drive system.

The xEV vehicle 10 illustrated in FIG. 2 may be powered or driven by thebattery system 20 alone, by the combustion engine 14 alone, or by boththe battery system 20 and the engine 14. It should be noted that, inother embodiments of the present approach, other types of vehicles andconfigurations for the vehicle drive system may be utilized, and thatthe schematic illustration of FIG. 2 should not be considered to limitthe scope of the subject matter described in the present application.According to various embodiments, the size, shape, and location of thebattery system 20, the type of vehicle, the type of xEV technology, andthe battery chemistry, among other features, may differ from those shownor described.

The battery system 20 may generally include one or more battery modules22, each having a plurality of battery cells (e.g., lithium ionelectrochemical cells), which are discussed in greater detail below. Thebattery system 20 may include features or components for connecting themultiple battery modules 22 to each other and/or to other components ofthe vehicle electrical system. For example, the battery system 20 mayinclude features that are responsible for monitoring and controlling theelectrical and thermal performance of the one or more battery modules22.

FIG. 3 illustrates a cutaway schematic view of another embodiment of thexEV 10 of FIG. 1, provided in the form of a mHEV 10 having the batterysystem 20. As discussed above, the battery system 20 for use with amicrohybrid system of an mHEV 10 may include a single battery thatprovides a first voltage (e.g. 12V) and a second voltage (e.g. 48V) andthat is substantially equivalent in size to a traditional 12V lead acidbattery used in traditional internal combustion vehicles. Hence, such abattery system 20 may be placed in a location in the mHEV 10 that wouldhave housed the traditional battery prior to conversion to an mHEV. Forexample, as illustrated in FIG. 3, the mHEV 10 may include the batterysystem 20A positioned similarly to a lead-acid battery of a typicalcombustion-engine vehicle (e.g., under the hood of the vehicle 10). Byfurther example, in certain embodiments, the mHEV 10 may include thebattery system 20B positioned near a center of mass of the mHEV 10, suchas below the driver or passenger seat. By still further example, incertain embodiments, the mHEV 10 may include the battery system 20Cpositioned below the rear passenger seat or near the trunk of thevehicle. It should be appreciated that, in certain embodiments,positioning a battery system 20 (e.g., battery system 20B or 20C) in orabout the interior of the vehicle may enable the use of air from theinterior of the vehicle to cool the battery system 20 (e.g., using aheat sink or a forced-air cooling design, as set forth in detail below).

FIG. 4 is a schematic view of an embodiment of the mHEV 10 of FIG. 3having an embodiment of the battery system 20 disposed under the hood ofthe vehicle 10. As previously noted and as discussed in detail below,the battery system 20 may further have dimensions comparable to those ofa typical lead-acid battery to limit or eliminate modifications to themHEV 10 design to accommodate the battery system 20. Further, thebattery system 20 illustrated in FIG. 4 is a three-terminal battery thatis capable of providing two different output voltages. For example, afirst terminal 24 may provide a ground connection, a second terminal 26may provide a 12V output, and a third terminal 30 may provide a 48Voutput. As illustrated, the 48V output of the battery module 22 may becoupled to a BAS 29, which may be used to start the internal combustionengine 33 during start-stop cycle, and the 12 V output of the batterymodule 22 may be coupled to a traditional ignition system (e.g., startermotor 28) to start the internal combustion engine 33 during instanceswhen the BAS 29 is not used to do so. It should also be understood thatthe BAS 29 may also capture energy from a regenerative braking system orthe like (not shown) to recharge the battery module 22.

It should be appreciated that the 48 V and 12 V outputs of the batterymodule 22 may also be provided to other components of the mHEV 10.Examples of components that may utilize the 48 V output in accordancewith present embodiments include radiator cooling fans, climate controlfans, electric power steering systems, active suspension systems,electric air-conditioning systems, auto park systems, cooled seats,electric oil pumps, electric super/turbochargers, electric water pumps,heated seats, heated windscreen/defrosters, and engine ignitions.Examples of components that may utilize the 12 V output in accordancewith present embodiments include window lift motors, vanity lights, tirepressure monitoring systems, sunroof motor controls, power seats, alarmsystems, infotainment online features, navigation features, lanedeparture warning systems, electric parking brakes, and external lights.The examples set forth above are not exhaustive and there may be overlapbetween the listed examples. Indeed, for example, in some embodiments,features listed above as being associated with a 48 V load may utilizethe 12 V output instead and vice versa.

In the illustrated embodiment, the 48 V output of the battery module 22may be used to power one or more accessories of the mHEV 10. Forexample, as illustrated in FIG. 4, the 48 V output of the battery module22 may be coupled to the heating, ventilation, and air conditioning(HVAC) system 32 (e.g., including compressors, heating coils, fans,pumps, and so forth) of the mHEV 10 to enable the driver to control thetemperature of the interior of the mHEV 10 during operation of thevehicle. This is particularly important in an mHEV 10 during idleperiods when the internal combustion engine 33 is stopped and, thus, notproviding any electrical power via engine charging. As also illustratedin FIG. 4, the 48 V output of the battery module 22 may be coupled tothe vehicle console 34, which may include entertainment systems (e.g.,radio, CD/DVD players, viewing screens, etc.), warning lights andindicators, controls for operating the mHEV 10, and so forth. Hence, itshould be appreciated that the 48 V output may, in certain situations,provide a more efficient voltage at which to operate the accessories ofthe mHEV 10 (e.g., compared to 12 V), especially when the internalcombustion engine 33 is stopped (e.g., during start-stop cycles). Itshould also be appreciated that, in certain embodiments, the 48 V outputof the battery module 22 may also be provided to any other suitablecomponents and/or accessories (e.g., lights, switches, door locks,window motors, windshield wipers, and so forth) of the mHEV 10.

Also, the mHEV 10 illustrated in FIG. 4 includes a vehicle controlmodule (VCM) 36 that may control one or more operational parameters ofthe various components of the vehicle 10, and the VCM 36 may include atleast one memory and at least one processor programmed to perform suchtasks. Like other components of the mHEV 10, the battery module 22 maybe coupled to the VCM 36 via one or more communication lines 38, suchthat the VCM 36 may receive input from the battery module 22, and morespecifically, the battery control module (BCM) of the battery module 22(discussed in detail below). For example, the VCM 36 may receive inputfrom the battery module 22 regarding various parameters, such as stateof charge and temperature, and the VCM 36 may use these inputs todetermine when to charge and/or discharge the battery module 22, when todiscontinue charging the battery module 22, when to start and stop theinternal combustion engine 33 of the mHEV 10, whether to use the BAS 29or the starter 28, and so forth.

FIGS. 5A-G are seven different views of an embodiment of the batterymodule 22 of FIG. 4. As mentioned above and discussed in detail below,the size and shape of the battery module 22 illustrated in FIGS. 5A-Gmay be similar to or exactly the same size and shape of a typicallead-acid battery. For example, a housing 39 of the battery module 22may conform to standardized dimensions for lead acid batteries. Tofacilitate discussion of the battery module 22 and the variousassemblies and components thereof, a Z axis 40 is defined as extendingthrough the length of battery module 22, a Y axis 42 is defined asextending through the height of the battery module 22, and an X axis 44is defined as extending through a width of the battery module 22.Further, the battery module 22 may be referred to as having two endportions 46 and 48 (e.g., capping ends along the Z axis 40), two sideportions 50 and 52 (e.g., capping ends along the X axis 44), a topportion 54, and a bottom portion 56 (e.g., capping ends along the Y axis42). Outer portions of the battery module 22 discussed in the presentdisclosure may cumulatively form the housing 39.

As mentioned above, the illustrated top portion 54 of the battery module22 may include three terminals (e.g., the ground terminal 24, the 12 Vpositive terminal 26, and the 48 V positive terminal 30) that, as setforth above, may be used to power various components of an xEV 10 duringoperation. As illustrated, in certain embodiments, the 48 V positiveterminal 30 may use a different type of connection (e.g., post,connector, or bracket 31) than the connection provided by the otherterminals (e.g., different sized posts 25 and 27), which may prevent thebattery module 22 from being improperly connected to an xEV 10 oranother load.

Furthermore, the top portion 54 of the battery module 22 may alsoinclude a suitable number of connections 58 (e.g., illustrated as fourDIN connectors) that may be used to couple the battery module 22 to theVCM 36, as discussed above, such that the VCM 36 may receive inputsregarding the status of the battery module 22 and/or provide controlinstructions to the battery module 22. Of course, in embodiments wherethe battery module 22 includes only two terminals, such as the groundterminal 24 and the 48V terminal 30, the communication port may onlyinclude two connections 58 that couple to a communication network suchas CAN or LIN, which may or may not connect to the VCM 36.

Additionally, as discussed in greater detail below, the top portion 54may include a plastic or composite cover 59, which may generally protectthe components of the battery control assembly (e.g., including thebattery control module (BCM) and a DC-to-DC converter, discussed below)that are disposed below the cover 59. Furthermore, as illustrated in atleast FIG. 5, the side portions 50 and 52 of the battery module 22include heat sink side plates 60 and 62. As set forth in greater detailbelow, these heat sink side plates 60 and 62 may function in conjunctionwith internal components of the battery module 22 (e.g., the internalheat fins, phase change material (PCM) layers, thermal foam layers, andso forth) to passively dissipate heat from the interior of the batterymodule 22 to the ambient environment external to the battery module 22.In other embodiments discussed below, one or more of the heat sink sideplates (e.g., heat sink side plates 60 and/or 62) may enable activecooling via one or more fans or liquid cooling blocks to enable enhancedtemperature control to the battery module 22.

FIG. 6 is an end exploded view of the embodiment of the battery module22 illustrated in FIGS. 5A-G. It may be appreciated that the batterymodule 22 illustrated in FIG. 6 has the plastic cover 59 and theconnectors 31, 25, and 27 (as discussed above) removed in order tobetter illustrate other assemblies and components of the battery module22. With these components removed, a view of the top portion 54 of thebattery module 22 shows a battery control assembly 70. The batterycontrol assembly 70 may include, for example, a battery control module(BCM) 72 that may generally monitor and control operation of the batterymodule 22. The BCM 72, which may also be referred to as a batterymanagement unit (BMU) 72, may comprise one or more circuit boards (e.g.,printed circuit boards (PCBs)) that may include a processor and memoryprogrammed to monitor and control the battery module 22 based on storedinstructions. For example, the BCM 72 may receive input from at leastone sensors disposed within the battery module 22 to determine at leastone temperature within the battery module 22. Based on the determinedtemperature(s), the BCM 72 may regulate (e.g., restrict or increase)power output of the battery module 22. Further, in certain embodiments,the BCM 72 may, for example, perform load balancing of the battery cellsof the battery module 22, control charging and discharging of thebattery cells of the battery module 22, determine a state of charge ofindividual battery cells and/or the entire battery module 22, activatean active cooling mechanism via one or more fans, liquid cooling blocks,thermoelectric system, heat pipes, or other cooling devices tofacilitate enhanced temperature control of the battery module 22.

The battery control assembly 70 illustrated in FIG. 6 also may include anumber of cables 74 that respectively couple one or more sensors (e.g.,temperature sensors, voltage sensors, current sensors, pressure sensors,or another suitable sensor) to the BCM 72 to provide information to theVCM 36 of the xEV 10 regarding the status of the battery module 22.Furthermore, in certain embodiments, the cables 74 may communicativelycouple the BCM 72 of the battery module 22 to the VCM 36 of an xEV 10such that the two control modules may work in tandem to, for example,regulate power usage in the vehicle 10, regulate power output of thebattery module 22, regulate the temperature of the battery module 22, orother suitable control activities with respect to the battery module 22.

The battery control assembly 70 illustrated in FIG. 6 also includes aDC-to-DC converter 76, as will be discuss in further detail in a sectionbelow. The DC-to-DC converter 76 may be any suitable power conversiondevice that may be used to provide one of the output voltages (e.g., 12V) of the battery module 22. That is, as set forth in detail below, thebattery cells of the battery module 22 may be coupled in series toprovide a first output voltage (e.g., 48 V), which may then betransformed to a different output voltage (e.g., 12 V) by the DC-to-DCconverter 76. In certain embodiments, the DC-to-DC converter 76 may becommunicatively coupled to and controlled by the BCM 72, which maydetermine or estimate a relative demand or priority for the two outputvoltages (e.g., when the mHEV 10 is starting or stopping the combustionengine), and may accordingly adjust the output of the DC-to-DC converter76 to provide more or less of the second output voltage. Further, it maybe appreciated that the illustrated 12 V DC-to-DC converter is merelyprovided as an example, and accordingly, in certain embodiments, theDC-to-DC converter 76 may output, for example, 3 V, 5 V, 10 V, 18 V, 20V, or another suitable output voltage. In other embodiments, multipleDC-to-DC converters 76 may be included in the battery module 22 suchthat the battery module 22 may have three or more output voltagesdistributed over four or more terminals. Additionally, in certainembodiments, the DC-to-DC converter 76 may not be integrated into thebattery module 22, but may instead be integrated into, for example, thexEV 10. The DC-to-DC converter 76 is discussed in greater detail below.

The exploded end portions 48 and 50 of FIG. 6 each illustrate an endassembly 80 of the battery module 22. Each end assembly 80 may include athermal gap pad 82 that is disposed directly over the interconnectedpower assembly 84, which is discussed in greater detail below. Each endassembly 80 also includes rectangular gaskets 86 and 88, which arerespectively disposed over the end portions 48 and 50 of the heat sinkside plates 60 and 62. Additionally, each end assembly 80 includes aninsulating polymer layer 90 (e.g., KAPTON® polyimide available fromDuPont™ or another suitable insulating polymer) that may be adhered toan end plate 92 of the end assembly 80 and/or the thermal gap pad 82.Further, the thermal gap pad 82, the insulating polymer layer 90, andthe end plate 92 of each end assembly 80 may include a vent feature 94(e.g., a circular hole of varying sizes) such that each correspondingvent feature 94 aligns with one another and with a vent disk 96 disposedbetween the insulating polymer layer 90 and the end plate 92 (e.g.,adhered to the end plate 92 by the insulating polymer layer 90). It maybe appreciated that the vent disk 96 may be a selective membrane thatmay allow, for example, air to be exchanged with the ambient environmentoutside the battery module 22 without allowing moisture or humidity toenter the battery module 22. Additionally, as discussed in greaterdetail below, the vent features 94 and the vent disk 96 may cooperate toproperly vent pressurized fluids if one or more of the battery cells ofthe interconnected power assembly 84 vents internal fluids. Finally, theend assemblies 80 may be coupled to the heat sink side plates 60 and 62and to a top compression plate 100 and a bottom compression plate 102,which are discussed in greater detail below, using a plurality of screws(not illustrated) and the illustrated screw holes in the end plates 92to seal the end assemblies to the remainder of the battery module 22.

FIG. 7 is another exploded view of the embodiment of the battery module22 illustrated in FIG. 6, less the plastic cover 59, the end assemblies80, cables 74, and connectors 58, discussed above. In FIG. 7, thebattery module 22 includes the BCM 72 and the DC-to-DC converter 76coupled to top plate 100 via a plurality of screws 101, as illustrated.The battery module 22 of FIG. 7 also includes a negative bus bar 104,which is configured to couple the DC-to-DC converter 76 to the negativeterminal 24 of the battery module 22, and is secured to the top plate100.

Additionally, as illustrated in FIG. 7, the heat sink side plates 60 and62 discussed above are each part of a side assembly 106. Each sideassembly 106 includes a heat sink side plate (e.g., heat sink sideplates 60 or 62) and a thermal gap pad 108 secured to the topcompression plate 100 and the bottom compression plate 102 using anumber of screws 110, as illustrated. The thermal gap pads 108 of theside plate assemblies 106 are thermally conductive and have a suitablethickness that enables good contact and efficient thermal conductionbetween the sides of the internal heat fins 112 of the power assembly 84(discussed in greater detail below) and the heat sink side plates 60 and62. By specific example, in certain embodiments, the thermal gap pad 108of the side assembly 106 may be a silicone elastomer (e.g., siliconerubber) impregnated with other materials (e.g., fiber glass), such as aSIL-PAD® elastomeric thermal interface (available from The BergquistCompany of Chanhassen, Minn.), or another suitable thermal gap padmaterial. It may be noted that, as discussed in detail below, when theside assemblies 106 are coupled to the top and bottom compression plates100 and 102, as illustrated, the power assembly 84 may be removedthrough the opened end portions 48 and 50 of the battery module 22(e.g., after removal of the end assemblies 80) without furtherdisassembly of the battery module 22.

As illustrated in FIG. 7, the power assembly 84 is disposed between thetop and bottom compression plates 100 and 102. The power assembly 84illustrated in FIG. 7 includes a stack of battery cell assemblies 114,wherein each battery cell assembly 114 includes a number of layersdiscussed in detail below. It may be appreciated that the stack ofbattery cell assemblies 114 of the power assembly 84 may include anumber of features, examples of which are set forth below, to enable thebattery module 22 to efficiently transfer heat away from the batterycell assemblies 114 and toward the heat sink side plates 60 and 62.Further, the power assembly 84 may additionally include other layers,such as the thermal gap pads 115, which may be disposed between thepower assembly 84 and the top and bottom compression plates 100 and 102.In certain embodiments, the power assembly 84 may include any suitablenumber of battery cell assemblies 114 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, or more) battery cell assemblies 114.

As illustrated in FIG. 7, each battery cell assembly 114 includes apouch battery cell 116 disposed within a frame 118 (e.g., a polymerframe) and a polymer film 120 (e.g., polyethylene terephthalate (PET))that may electrically isolate the pouch battery cell 116 from theinternal heat fin 112. As discussed in detail below, each of theillustrated frames 118 include registration features 121 (e.g.,alternating cup-like protruding and inset features), discussed in detailbelow, that may align each battery cell 116 to enable a uniform powerassembly 84. On top of the pouch battery cell 116, a thermal gap pad 122is disposed, followed by a phase change material (PCM) layer 124. Thestructure and properties of the various layers of the battery cellassembly 114 is discussed in detail below with respect to FIG. 12.

Additionally, as illustrated in FIG. 7, the battery module 22 alsoincludes two interconnect assemblies 128 that may, in combination,couple each of the battery cells 116 of the power assembly 84.Specifically, tab electrodes 129 of the battery cells 116 may becommunicatively coupled in series or in parallel. In particular, eachillustrated interconnect assembly 128 may include a component, referredto herein as a cell interconnect board 130, which may provide structuralsupport for the interconnection of the battery cells 116 and a number ofsensors 132 (e.g., temperature sensors, voltage sensors, currentsensors, pressure sensors, or another suitable sensor). Each cellinterconnect board 130, which may be manufactured from a printed circuitboard (PCB), may include a number of slots 134. These slots 134 mayallow the tab electrodes 129 (discussed in greater detail below) ofneighboring battery cells 116 of the power assembly 84 to pass throughthe cell interconnect board 130 as the cell interconnect board 130 iscoupled to the top compression plate 100 and the bottom compressionplate 102 via the screws 136. Further, after traversing the slots 134 ofthe cell interconnect board 130, the tab electrodes 129 neighboringbattery cells 116 in the power assembly 84 may be coupled to one anotherusing, for example, using the interconnection devices 138, which areillustrated as clamps in FIG. 7. In certain embodiments, theinterconnection devices 138 may be coupled to the cell interconnectboard 130 using pins or screws. Additionally, in certain embodiments,the interconnection devices 138 may further electrically couple to theone or more of the sensors 132 (e.g., current and/or voltage sensors)disposed on the cell interconnect board 130 to enable measurements ofparticular battery cells 116 in the power assembly 84, as discussedfurther below.

The embodiment of the battery module 22 illustrated in FIG. 7 alsoincludes four compression bolts 140. Each illustrated compression bolt140 passes through an opening in the top compression plate 100, throughan opening in a registration feature 121 of the frames 118 surroundingeach battery cell 116 of the power assembly 84, and extend to enablescrewing into a locked nut feature 142 disposed in the bottomcompression plate 102. The compression bolts 140 generally serve tocompress the power assembly 84 such that each of the layers of thevarious battery cell assemblies 114 of the power assembly 84 are inintimate contact with one another (e.g., to encourage efficient thermaltransfer). Accordingly, in certain embodiments, the compression bolts140 may be torque-limited to prevent over tightening and/or overcompression of the power assembly 84. It may also be appreciated thatthe compression bolts 140 further ensure that the frames 118 surroundingeach battery cell 116 remain aligned or registered with one another, forexample, as the battery module 22 is tilted and/or subjected tovibrations. In other embodiments, other compression methods may be used,as set forth in detail below.

Lithium Ion Battery with Lead Acid Form Factor

Present embodiments may provide non-lead acid batteries with formfactors of standard lead acid batteries. For example, presentembodiments include a single lithium ion battery system that providestwo voltages (e.g., 12V and 48V) from a package having a form factorwithin boundaries defined for standardized lead acid batteries (e.g.,standard 12V lead acid batteries). Accordingly, present embodiments mayfacilitate retrofitting systems (e.g., vehicles) designed to accommodatetraditional lead acid batteries. For original equipment manufacturers,such as vehicle manufacturers, systems in accordance with presentembodiments may be installed as original equipment in the place ofconventional lead acid batteries with little or no alteration in thelocation or physical configuration of support structures and electricalconnections. The presently disclosed embodiments may thus be used inconnection with conventional internal combustion engines, hybridvehicles, electric vehicles, and so forth. Moreover, present embodimentsmay be used for non-vehicular applications, such as for home or buildingenergy storage, energy generation systems (e.g., wind or enginegenerators) and so forth.

Turning to FIG. 5A, present embodiments include the battery module 22,which may be considered generally representative of a battery modulethat is a non-lead acid battery (e.g., a battery module includingultracapacitors, nickel-zinc batteries, nickel-metal hydride batteries,and lithium batteries). In particular, the battery module 22 illustratedin FIG. 5A is a lithium ion battery module. Further, the battery module22 is a lithium ion battery module with an overall geometry ordimensions that conform to the overall dimensions of a standard leadacid battery. In other words, the battery module 22 has overalldimensions (e.g., length, width, and height) that generally correspondto or fit within maximum overall dimensions for a standard lead acidbattery. Specifically, the battery module 22 in the illustratedembodiment has dimensions that conform to the dimensions for a standardlead acid battery having DIN (Deutsches Institut für Normung) code H6,which is a European standard. However, in accordance with presentembodiments, the battery module 22 may include a lithium ion batterymodule or other non-lead acid battery that conforms to any of variousdifferent lead acid dimensional standards, which may be generallyreferred to as falling within certain standardized form factors.

As generally suggested above, certain industry standards have beendeveloped for use in configuring the physical packaging of lead acidbatteries for many applications. For example, the Battery CouncilInternational (BCI) is a trade association that sets certain standardsfor vehicle batteries. A number of battery groups and sizes have beenspecified by the BCI. The listings below provide examples of certain ofthese, including European standards (e.g., DIN code H6):

BCI/DIN/EN Reference Chart European Reference Information MaximumDimensions - Millimeters DIN Code EN Code L W H T6 LB3 66LB 278 175 175T65 N/A 54LB 293 175 175 T5 LB2 45LB 242 175 175 H5 L2 55L2 242 175 190H6 L3 66L3 278 175 190 H8 L5 88L5 354 175 190 T5 LB2 45LB 242 175 175 T6LB3 66LB 278 175 175 T7 LB4 77LB 315 175 175 T8 LB5 88LB 354 175 175 H7L4 77L4 315 175 190 H9 L6 394 175 190 T5 LB2 45LB 242 175 175 H5 L2 55L2252 175 190 H6 L3 66L3 283 175 190 T4 LB1 36LB 207 175 175 T4 LB1 36LB210 175 175 H3 L0 32L0 175 175 190 H4 L1 45L1 207 175 190 TypicalMaximum Overall Dimensions BCI Group Millimeters Inches Number L W H L WH PASSENGER CAR AND LIGHT COMMERCIAL_BATTERIES 12-VOLT (6 CELLS) 21 208173 222 8 3/16 6 13/16 8¾ 22F 241 175 211 9½ 6⅞ 8 5/16 22HF 241 175 2299½ 6⅞ 9 22NF 240 140 227 9 7/16 5½ 8 15/16 22R 229 175 211 9 6⅞ 8 5/1624 260 173 225 10¼ 6 13/16 8⅞ 24F 273 173 229 10¾ 6 13/16 9 24H 260 173238 10¼ 6 13/16 9⅜ 24R 260 173 229 10¼ 6 13/16 9 24T 260 173 248 10¼ 613/16 9¾ 25 230 175 225 9 1/16 6⅞ 8⅞ 26 208 173 197 8 3/16 6 13/16 7¾26R 208 173 197 8 3/16 6 13/16 7¾ 27 306 173 225 12 1/16 6 13/16 8⅞ 27F318 173 227 12½ 6 13/16 8 15/16 27H 298 173 235 11¾ 6 13/16 9¼ 29NF 330140 227 13 5½ 8 15/16 31 325 167 238 12 13/16 6 9/16 9⅜ 31A 325 167 23812 13/16 6 9/16 9⅜ 31T 325 167 238 12 13/16 6 9/16 9⅜ 33 338 173 238 135/16 6 13/16 9⅜ 34 260 173 200 10¼ 6 13/16 7⅞ 34/78 260 175 200 10 1/166⅞ 7⅞ 34R 260 173 200 10¼ 6 15/16 7⅞ 35 230 175 225 9 1/16 6⅞ 8⅞ 36R 263183 206 10⅜ 7¼ 8⅛ 40R 277 175 175 10 15/16 6⅞ 6⅞ 41 293 175 175 11 3/166⅞ 6⅞ 42 243 173 173 9 5/16 6 13/16 6 13/16 43 334 175 205 13⅛ 6⅞ 8 1/1645 240 140 227 9 7/16 5½ 8 15/16 46 273 173 229 10¾ 6 13/16 9 47 246 175190 9 11/16 6⅞ 7½ 48 306 175 192 12 1/16 6⅞ 7 9/16 49 381 175 192 15 6⅞7 3/16 50 343 127 254 13½ 5 10  51 238 129 223 9⅜ 5 1/16 8 13/16 51R 238129 223 9⅜ 5 1/16 8 13/16 52 186 147 210 7 5/16 5 13/16 8¼ 53 330 119210 13 4 11/16 8¼ 54 186 154 212 7 5/16 6 1/16 8⅜ 55 218 154 212 8⅝ 61/16 8⅜ 56 254 154 212 10 6 1/16 8⅜ 57 205 183 177 8 1/16 7 3/16 6 15/1658 255 183 177 10 1/16 7 3/16 6 15/16 58R 255 183 177 10 1/16 7 3/16 615/16 59 255 193 196 10 1/16 7⅝ 7¾ 60 332 160 225 13 1/16 6 5/16 8⅞ 61192 162 225 7 9/16 6⅜ 8⅞ 62 225 162 225 8⅞ 6⅜ 8⅞ 63 258 162 225 10 3/166⅜ 8⅞ 64 296 162 225 11 11/16 6⅜ 8⅞ 65 306 190 192 12 1/16 7½ 7 9/16 70208 179 196 8 3/16 7 1/16 7 11/16 71 208 179 216 8 3/16 7 1/16 8½ 72 230179 210 9 1/16 7 1/16 8¼ 73 230 179 216 9 1/16 7 1/16 8½ 74 260 184 22210¼ 7¼ 8¾ 75 230 179 196 9 1/16 7 1/16 7 11/16 75/25 238 173 197 9⅜ 613/16 7¾ 76 334 179 216 13⅛ 7 1/16 8½ 78 260 179 196 10¼ 7 1/16 7 11/1685 230 173 203 9 1/16 6 13/16 8 86 230 173 203 9 1/16 6 13/16 8 90 246175 175 9 11/16 6⅞ 6⅞ 91 280 175 175 11 6⅞ 6⅞ 92 317 175 175 12½ 6⅞ 6⅞93 354 175 175 15 6⅞ 6⅞ 95R 394 175 190 15 9/16 6⅞ 7½ 96R 242 173 175 99/16 6 13/16 6⅞ 97R 252 175 190 9 15/16 6⅞ 7½ 98R 283 175 190 11 3/16 6⅞7½ PASSENGER CAR AND LIGHT COMMERCIAL BATTERIES 6-VOLT(3 CELLS) 1 232181 238 9⅛ 7⅛ 9⅜ 2 264 181 238 10⅜ 7⅛ 9⅜ 2E 492 105 232 19 7/16 4⅛ 9⅛ 2N254 141 227 10 5 9/16 8 15/16 17HF 187 175 229 7⅜ 6⅞ 9 HEAVY-DUTYCOMMERCIAL BATTERIES 12-VOLT (6 CELLS) 4D 527 222 250 20¾ 8¾ 9⅞ 6D 527254 260 20¾ 10 10¼ 8D 527 283 250 20¾ 11⅛ 9⅞ 28 261 173 240 10 5/16 613/16 9 7/16 29H 334 171 232 13⅛ 6¾ 9 1/8 10 30H 343 173 235 13½ 6 13/169 1/4 10 31 330 173 240 13 6 13/18 9 7/16 ELECTRIC VEHICLE BATTERIES6-VOLT (3 CELLS) GC2 264 183 270 10⅜ 7 3/16 10⅝ GC2H 264 183 295 10⅜ 73/16 11⅝

The listings set forth above are not exhaustive and the battery module22 may generally be representative of a non-lead acid battery thatconforms to other standardized form factors for lead acid batteries. Itshould also be noted that a number of variations in the form factorslisted above may be due to such factors as rated voltages, capacity,application, the physical mounting requirements (which may vary fordifferent original equipment manufacturers), the terminal types andconfigurations, the country or region, and so forth. Terminals may beplaced, for example, in top, front, side or a combination of locations.Hold-down ledges (e.g., footings) and features may similarly vary withthe different enclosures.

In some embodiments, the housing 39 of the battery module 22 may besubstantially smaller than the standard dimensions for a lead acidbattery. Accordingly, various adapters, shims, and so forth may be usedto more closely conform to existing mounting structures for lead acidbatteries. Such adapters and similar hardware may be designed to allowthe battery module 22 to fit within particular systems (e.g., vehicles).These adapters may fit on sides, the base, the top, or generallyanywhere on the housing 39 that may not directly conform to the desiredmounting position or structures.

The particular outside geometry and configuration of internal featuresof the battery module 22, such as the power assembly 85, may be adaptedbased on the available space and layout dictated by the standard leadacid battery dimensions to which the housing 39 of the battery module 22conforms. Indeed, many variations of such structures may be designed andimplemented in accordance with present embodiments. Specifically, forexample, present embodiments include certain arrangements andconfigurations of external and internal features in conformance with theoverall dimensions of a desired lead acid battery standard while stillachieving certain performance goals. For example, to more efficientlyutilize available space for heat transfer, present embodiments mayinclude side portions (e.g., heat sink side plates 60 and 62, end plates92) that substantially extend to the outermost limits of standarddimensions for a lead acid battery. This may include extending a largepercentage (e.g., 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%) ofthe maximum available distance within the standard and even all the way(100%).

Present embodiments may also include, for example, configurations forproviding internal space within the housing 103 to accommodate a numberof battery cells 116 and/or the battery control assembly 84 such thatone or more voltages beyond or differing from what would be provided bya standard lead acid battery of the same size can be provided whilestill conforming to the associated standardized dimensions of thestandard lead acid battery. Present embodiments may also be configuredto accommodate certain heat transfer goals by including lengthenedinternal heat fins 112 or lengthened heat sink side plates 60 and 62.Utilizing available space to facilitate heat transfer or incorporateinternal battery components (e.g., lithium ion components) may alsoresult in changes relative to typical lead acid battery configurations,such as elimination of recesses along the sides or elimination ofcertain attachment features.

As a specific example of certain configuration aspects discussed above,in the illustrated embodiment, certain features of the housing 39substantially extend in at least one direction to an outermost dimensionof a standard lead acid battery. Such features include the end plates92, the heat sink side plates 60 and 62 (or heat sink outer wallfeature), the plastic or composite cover 59, the bottom compressionplate 102, aspects of such features, and so forth. As an example ofextending in at least one direction to an outermost dimension of astandard lead acid battery, an outer surface of an outer wall (e.g., endplate 92) of the housing 39 may extend (relative to a correspondingopposite surface) to an outer boundary of a standard length dimensionassociated with a particular lead acid battery code or standard. Aspreviously noted, the illustrated battery module 22 conforms with DINcode H6, which has a maximum length dimension of 278 millimeters (10.94inches), a maximum width dimension of 175 millimeters (6.88 inches), anda maximum height dimension of 190 millimeters (7.48 inches). Asillustrated by FIG. 5A, the length 150, width 152, and height 154dimensions of the battery module 22 are approximately 277.11 millimeters(10.91 inches), 173.99 millimeters (6.85 inches), and 189.99 (7.48inches), respectively. Thus, the battery module 22 conforms to thedimensions associated with DIN code H6 and substantially extends in thelength, width, and height dimensions to the corresponding maximumdimensions of DIN code H6.

Specifically, for example, a length of the heat sink outer wall feature,which includes the heat sink side plates 60 and 62 in the illustratedembodiment, substantially extends to the maximum length dimension forDIN code H6. Indeed, each of the heat sink side plates 60 and 62 may beapproximately 10.71 inches in length. This extension substantially tothe standard limit may prevent inclusion of a recessed area between thetop portion 54 and the bottom portion 55 (e.g., a recessed battery wallrelative to a base and top cover). Further, in conjunction with otherfeatures of the housing (e.g., the end plates 92), such an extension mayprevent inclusion of features for coupling with the battery module 22.However, such an extension may also accommodate various features of thebattery module 22, such as by providing extra space for certainfunctional features within the available standardized area. For example,the extra space may facilitate inclusion of heat transfer features alongthe outside of the heat sink side plates 60 and 62. Also, the associatedadded internal length may accommodate the cell interconnect boards 130,which may be spaced apart to enable positioning of battery cells 116 inbetween and to properly align with tab electrodes 129 extending from thebattery cells. Similarly, the space may be utilized to accommodate theinternal heat fins 112, the PCM 124, and so forth.

As specific example of space utilization in accordance with presentembodiments, it is noted that heat transfer features 156 (e.g., fins) onthe heat sink side plates 60 and 62 are spaced apart by approximately4.32 millimeter (0.17 inches) and have a thickness of approximately 0.25millimeters (0.1 inches) in the illustrated embodiment. Thus, theadditional space provided by extending the heat sink side plates 60 and62 substantially to the outer dimensional boundaries of the standard(lead acid battery standard) provides room for additional heat transferfeatures 156 that can be used to achieve a desired overall level of heattransfer. It should be noted that the end plates 92 may be coupled tothe distal ends of the heat sink outer wall feature to further extendtoward the standard boundaries, as illustrated in FIG. 6. Further, itshould be noted that, while the heat sink outer wall feature ispresently described and illustrated as including the heat sink sideplates 60 and 62, in other embodiments it may include a single suchplate or multiple plate components.

Also, the heat transfer features 156, which include fins or ridges thatrun or extend along a majority of the height of the housing 39, alsoextend outward from the heat sink side plates 60 and 62 along the X axis44 by a certain amount (e.g., approximately 9.9 millimeters (0.39inches)). These heat transfer features 156 may have a consistentalignment along the length of each of the heat transfer features 156such that a consistent outer boundary is defined by the outer surfacesof the heat transfer features 156. These outer boundaries of the heattransfer features 156 on both heat sink side plates 60 and 62 maysubstantially extend to the outer dimensions of a lead acid batterystandard. This substantially consistent extension to the width dimensionalong the height of the battery module 22 is in contrast to traditionalbatteries that have recessed sidewalls. The distance between outersurfaces of heat transfer features 156 on the heat sink side plate 60and outer surfaces of heat transfer features 156 on the heat sink sideplate 62 may substantially extend to the width dimension for a standardlead acid battery. In other words, outer edges of the two heat sink sideplates 60 and 62 are spaced apart by a distance substantially equal toan outermost width dimension of the standard. The extra heat transfercapability achieved by extending the heat transfer features 156 in thismanner may facilitate inclusion of footings 160 under a subset 162 ofheat transfer features 156 that are shortened relative to other heattransfer features 156, as illustrated in FIG. 5A. Indeed, the subset 162may have a height of approximately 129.53 millimeters (5.1 inches)relative to other heat transfer features 156 that generally have aheight of approximately 162.56 millimeters (6.4 inches). There may beapproximately 27.94 millimeters (1.1 inches) (e.g., approximately 15% ofthe overall height of the battery module 22) of space between the bottomof the subset 162 and the bottom portion 56 for incorporation of thefootings 160.

As noted above, the battery module 22 includes footings 160. Thefootings 160 facilitate coupling or securing of the battery module 22 toa support (e.g., a battery receptacle in a vehicle) and are generallyaligned with the bottom portion 56. The footings 160 are included on twosides of the battery module 22 and excluded on the other sides.Specifically, in the illustrated embodiment, the footings 160 arepositioned on the same sides as the heat sink side plates 60 and 62.However, no footings are included on the sides with the two end portions46 and 48 (e.g., end plates 92). In other embodiments this relationshipmay be reversed. While a typical lead acid battery may include footingson all sides, present embodiments may utilize the space that would betaken up by including the excluded footings to accommodate the endplates 92. Indeed, protuberances 166 in the end plates 92, which aregenerally U-shaped in the illustrated embodiment, provide structuralintegrity for the end plates 92 and accommodate buses 180 and 182, maysubstantially extend outward along the Z axis 40 to a maximum lengthdimension for a standard lead acid battery. In other words, the spacebetween the outermost surfaces of the protuberances on the end plates 92for the ends of the battery module 22 may be spaced apart by a distancesubstantially equal to the maximum length dimension for the lead acidbattery standard. Because the end plates 92 are substantially planar andbase portions of the end plates 92 substantially align with the bottomportion 56, no space is available for footings at the ends along the Zaxis 40. This positioning of the end plates 92 may be desirable foraccommodation of internal components, such as accommodation of a lengthof the battery cells 116, accommodation of positioning of cellinterconnect boards 130, accommodation of extra length for the heat fins112 or the PCM 124, and so forth.

As noted above, the battery module 22 may include a lithium ion batteryand the housing 39 may have dimensions that conform to overalldimensions for a standard lead acid battery. The battery module 22 mayalso include the top compression plate 100, the bottom compression plate102, and a plurality of lithium ion battery cells 116 arranged in astack within the housing 39 and between the top compression plate 100and the bottom compression plate 103. Furthermore, to facilitatefunctionality beyond the nature of a particular standard lead acidbattery, yet within the same standard dimension, the battery module 22may include the battery control assembly 70. This battery controlassembly 70, which may include the BCM 72, cables 74, and the DC-to-DCconverter 76, may enable provision of multiple different voltages fromdifferent terminals of the battery module 22. The negative terminal 24may couple (e.g., via one of the busses 180 and 182) with an anode ofthe stack of battery cells 116, the first positive terminal 26 maycouple with a cathode of the stack of battery cells 116, and the secondpositive terminal 30 may coupled with the DC-to-DC converter 76, whichmay in turn couple with the cathode of the stack of battery cells 116.While the illustrated battery module 22 includes a three terminalbattery that utilizes the terminal 24 as a common ground between twovoltage networks, in other embodiments the voltage networks may beisolated through the DC-to-DC converter and provide four terminals.Furthermore, to facilitate access and maintain the overall form factorof a standard lead acid battery, the battery control assembly (e.g., theBCM 72) is disposed within the housing 39 on a side of the topcompression plate 100 opposite the plurality of lithium ion batterycells 116.

One or more of the disclosed embodiments, alone or in combination, mayprovide one or more technical effects useful in the manufacture,assembly (e.g., retrofitting) and defining of operationalcharacteristics of battery modules. For example, certain embodiments ofthe present approach may enable improved capabilities relative to thecapabilities of a standard lead acid battery but within standardizeddimensions for the standard lead acid battery. This may facilitateinclusion of updated batteries in systems designed for traditional leadacid batteries. By specific example, providing a stack of lithium ioncells within a housing that incorporates heat transfer featuresextending substantially to the maximum standard dimensions of a leadacid battery and a DC-to-DC converter, present embodiments may offersubstantially improved functionality (e.g., supply of multiple differentvoltage levels) within the same package compared to traditional leadacid battery systems. The technical effects and technical problems inthe specification are exemplary and are not limiting. It should be notedthat the embodiments described in the specification may have othertechnical effects and can solve other technical problems.

Battery Module with Cooling Features

FIGS. 8-10 illustrate different embodiments of heat sink outer wallfeatures of the battery module 22. Each of the heat sink outer wallfeatures of FIGS. 8-10 may correspond to or replace one or both of theheat sink side plates 60 and 62, as illustrated in FIGS. 5-7.Accordingly, it may be appreciated that, any of the heat sink side plateembodiments illustrated in FIGS. 8-10 may be used in variouscombinations on the first or second side portions 50 and 48 of thebattery module 22. Further, as set forth below, the heat sink side plateembodiments set forth in FIGS. 8-10 may provide passive cooling, activecooling, or combinations thereof. It may be appreciated that a number ofthe features discussed below (e.g., the heat sink side plates 60 and 62,the internal heat fins 112, the PCM layers 124, the thermal gap pads108, 122, and 115, the housing 39, sensors 132, and/or the batterycontrol module 72) may be collectively referred to in variouscombinations as the thermal management system of the battery module 22.

For example, FIG. 8 illustrates the heat sink side plate 60 (or 62),which is a passive cooling device. The illustrated heat sink side plate60 may be manufactured from a metal or alloy, such as steel, aluminum,copper, nickel, tin, or another suitable metal or alloy. In particular,the heat sink side plate 60 illustrated in FIG. 8 includes 39 externalheat fins 252 as well as two mounting plates 253 positioned at oppositeends of the heat sink side plate 60. The illustrated external heat fins252 are disposed vertically along the outer side 254 of the heat sinkside plate 60 and are configured to radiate heat from the power assembly84 of the battery module 22 to the ambient environment outside thebattery module 22. For example, as set forth in detail below, theinternal heat fins 112 of the power assembly 114 may be positioned to bein thermal contact (e.g., thermal communication) with an inner side 256of the heat sink side plate 60. As such, as each battery assembly 114imparts thermal energy to the inner side 256 of the heat sink side plate60, the external heat fins 252 of the heat sink side plate dissipatesthe received thermal energy into the environment surrounding the batterymodule 22.

It may be appreciated that, in certain embodiments, a heat sink sideplate 60 of FIG. 8 may include any number of (e.g., 5, 10, 15, 20, 25,30, 35, 40, 45, 50 or more) external heat fins 252 arranged vertically,horizontally, diagonally, or any combination thereof. It may also beappreciated that the vertical orientation of the illustrated externalheat fins 252 may facilitate the convection (e.g., heat-drivencirculation) of a cooling fluid (e.g., air) between the external heatfins 252 to enable better passive cooling of the battery module 22 thanhorizontal or diagonal fins may provide. In certain embodiments, theexternal heat fins 252 may also be tapered to enable better heat flow.For example, in an embodiment with a vertical arrangement of externalheat fins 252, the external heat fins 252 may be wider in the bottom andnarrower on top to enable a jet stream flow of cooling fluid (e.g., air)from bottom to top. In certain embodiments, the spacing 258 between theexternal heat fins 252 may be approximately 2 mm, 3 mm, 4 mm, 5 mm, 6mm, 7 mm, 8 mm, 9 mm, 10 mm, or more. In certain embodiments, theexternal heat fins 252 may extend away from a back plate 260approximately 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, ormore. Further, in certain embodiments, the fins 252 may have a thickness262 of 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5mm, or more. In certain embodiments, the fins 252 may have a thicknessof greater than or equal to 0.3 mm, while the spacing 258 between thefins 258 may be greater than or equal to approximately 1 mm.

FIG. 9 illustrates an embodiment of a heat sink side plate 264 that issimilar to the heat sink side plate 60 illustrated in FIG. 8, but withadditional active cooling features. That is, in addition to the externalheat fins 252 extending from the back plate 260 discussed above, theheat sink side plate 264 illustrated in FIG. 9 includes two cooling fans266 that are coupled to the heat sink side plate 264. It may beappreciated that certain embodiments of the heat sink side plates 264may lack the external heat fins 252 altogether. During operation, inaddition to the airflow provided by convection, the cooling fans 266provide additional cooling airflow to maintain the temperature of thebattery module 22. In certain embodiments, the operation of the coolingfans 266 may be controlled by the BCM 72 of the battery module 22 or bythe VCM 36 of an xEV 10, as illustrated in FIG. 4, such that the coolingfans 266 are only operated when the battery module 22 is at or above aparticular threshold temperature.

FIG. 10 illustrates an embodiment of an active cooling heat sink sideplate 270 having a liquid cooling block 272 attached to the back plate260. Additionally, the liquid cooling block 272 of the heat sink sideplate 270 includes a liquid input port 274 and a liquid output port 276.While the embodiment of FIG. 10 illustrates the liquid input port 274and the liquid output port 276 as being positioned at the bottom of theheat sink side plate 270, in other embodiments, these ports 274 and 276may be positioned anywhere (e.g., top, middle, or near the end portions)on the heat sink side plate 270. During operation, a liquid coolant isdelivered to the liquid cooling block 272 via the liquid input port 274,and the liquid coolant subsequently traverses an internal cavity of theliquid cooling block 272 to absorb heat from the battery module 22. Incertain embodiments, the internal cavity of the liquid cooling block 272may include a number of internal fins, ribs, ducts, and/or channels thatare arranged to provide a particular flow path through the liquidcooling block 272 for the coolant liquid to flow. After traversing theliquid cooling block 272, the heated liquid coolant may exit the liquidcooling block 272 via the liquid output port 276. In certainembodiments, the flow of the liquid coolant may be driven by convectionalone, while in other embodiments, an active mechanism (e.g., a pump)may be used. In certain embodiments, after exiting the liquid outputport 276 of the liquid cooling block 272, the liquid coolant may bedirected to a radiator or a similar cooling device before being returnedto the liquid input port 274 of the liquid cooling block 272 once again.Further, in other embodiments, the liquid cooling block 272 may includea front plate (e.g., like the back plate 260, but disposed on a frontface 278 of the liquid cooling block 272) that may be coupled to asecond battery module such that a single liquid cooling block 272 may beused to cool both battery modules. It may be appreciated that the liquidcooling block 272 is merely provided as an example, and in otherembodiments, other suitable devices (e.g., thermoelectric devices) mayalso be used to control the temperature of the battery module 22. It mayalso be appreciated that, in certain embodiments, the battery module 22may utilize a liquid cooling block 272 and a heated fluid (or athermoelectric device) to warm the battery module 22 for improvedoperation in colder environments.

To better illustrate other features of the thermal management system ofthe battery module 22, FIG. 11 is a cross-sectional view of the batterymodule 22 of FIG. 5A taken along line 11-11. For the embodiment of thebattery module 22 illustrated in FIG. 11, the housing 39 of the batterymodule 22 (e.g., including the top compression plate 100, the bottomcompression plate 102, and the heat sink side plates 60 and 62) isdisposed around the power assembly 84 of the battery module 22. Asillustrated, the heat sink side plates 60 and 62 are respectivelycoupled to the top compression plate 100 and the bottom compressionplate 102 by the screws 110. Further, thermal gap pads 108 arerespectively positioned below the heat sink side plates 60 and 62,against the stacked curved side portions 280 of the internal heat fins112 of the power assembly 84. It should also be appreciated that, incertain embodiments, since the housing 39 of the battery module 22 maybe manufactured from a metal or alloy (e.g., steel, aluminum, copper,tin, nickel, or another suitable metal or alloy), the entire housing 39of the battery module 22 may radiate or otherwise dissipate heat fromthe power assembly 84 during operation.

It should be appreciated that the housing 39 may include one or morecompression management features to compress the individual batteryassemblies 114 of the power assembly 84 of the battery module 22. Incertain embodiments, as previously discussed, the compression bolts 140may pass through a portion of the top compression plate 101, extendthrough one or more registration features 121 of the frames 118 of eachbattery cell 116, and thread into portions of the bottom compressionplate 102 (e.g., in a torque limited fashion) to compress the powerassembly 84. In other embodiments, as illustrated in FIG. 11, the topcompression plate 39 may include an expansion bolt 277 that may extendbetween a top portion 279 and a bottom portion 281 of the topcompression plate 100. As illustrated, the top portion 279 and thebottom portion 281 may be implemented as two separate plates, in whichthe top portion 279 is fixed relative to the housing 39, while thebottom portion 281 is able to move. Upon tightening the expansion bolt277, the bottom portion 281 of the top compression plate 100 may beforced away from the top portion 279 of the top compression plate 100(e.g., along the Y axis 42), which may compress the power assembly 84(e.g., along the Y axis 42). It may be appreciated that, in certainembodiments, the compression features 277, 279, and 281 may be include,additionally or alternative, in the bottom compression plate 102 toprovide at least partially compress the power assembly 84.

It may be appreciated that the various thermal gap pads (e.g., thermalgap pads 108, 115, and 122) used throughout the illustrated batterymodule 22 may generally provide a number of functions. That is, thethermal gap pads 108, 115, and 122 are thermally conductive layers(e.g., such as a SIL-PAD® elastomeric thermal interface), enabling arelatively high-efficiency heat transfer across the thermal gap pads.Further, the thermal gap pads 108, 115, and 122 may each generallyenable good thermal contact (e.g., limiting or preventing insulating airgaps) between components disposed on opposite sides of the thermal gappads (e.g., directly between the curved side portions 280 of theinternal heat fins 112 and the heat sink side plates 60 and 62, directlybetween the battery cell 116 and the PCM layer 124, and directly betweenthe top and bottom of the power assembly 84 and the battery housing 39).In particular, the thermal gap pads 108, 115, and 122 may be a foam-likematerial that ensures good contact between components by expanding andcontracting to account for manufacturing variability and/or surfacedeformities of the components of the battery module 22 (e.g., a slightlythicker or thinner battery cell 116). For example, the thermal gap pads115 and 122 may serve as spring elements that enable a uniform pressureto be provided to each battery cell 116 of the power assembly 84 of thebattery module 22. Additionally, in certain embodiments, the thermal gappads 108, 115, and 122 may also provide at least some vibrationdampening for the components disposed near the thermal gap pads 108,115, and 122. Further, it may be appreciated that, in certainembodiments, each of the thermal gap pads 108, 115, and 122 may bemanufactured from a particular material and/or have a particular set ofdimensions to provide the desired heat transfer, expansion/compression,and/or vibration absorption properties.

As discussed above, in certain embodiments, the power assembly 84 of thebattery module 22 may include a plurality of battery assemblies 114.Additionally, each illustrated battery assembly 114 of FIG. 11 includesan internal heat fin 112, insulating polymer layer 120, a battery cell116, a thermal gap pad 122, and a PCM layer 124, disposed directly atopone another in a tightly packed horizontal stack. In other words, theillustrated power assembly 84 includes a plurality of internal heat fins112 that are interleaved or interdigitated with the plurality of batterycells 116. While the illustrated embodiment of FIG. 11 provides ahorizontal stack of battery assemblies 114, in other embodiments, thepower assembly 84 may be provided as a vertical stack of batteryassemblies 114 without negating the effect of the present approach.Further, as mentioned above, FIG. 11 illustrates the curved sideportions 280 of the internal heat fins 112, which are compressed againstthe thermal gap pads 108 below the heat sink side plates 60 and 62,respectively. It may be appreciated that the curved side portions 280may enable the internal heat fins 112 to have greater overlap, andaccordingly better heat transfer (e.g., improved thermal contact orcommunication), with the heat sink side plates 60 and 62 than would beprovided if the curved side portions 280 were not present. In otherembodiments, the internal heat fins 112 may have an angled portion(e.g., a right angled portion) to provide this overlap without the useof the curved side portions 114 illustrated in FIG. 11.

With the foregoing in mind, FIG. 12 is an exploded schematic of anembodiment of a battery cell assembly 114. It should be appreciated thatthe various components of the battery cell assembly illustrated in FIG.12 are configured to form a stack (e.g., a horizontal “pancake” stack ora vertical “bookshelf” stack); therefore, while the present discussionmay be directed toward a horizontal stack, this is merely provided as anon-limiting example. As illustrated in FIG. 12, in certain embodiments,the battery cell assembly 114 may include the internal heat fin 112,having the curved side portions 280 to enhance heat transfer to the heatsink side plates 60 and 62, as set forth above. Additionally, forembodiments in which the internal heat fin 112 is also electricallyconductive (e.g., for an internal heat fin 112 manufactured from ametal, alloy, HOPG, or another conductive material), the electricallyinsulating polymer layer 120 (e.g., a polyimide electrically insulatinglayer) may be positioned directly between the internal heat fin 112 andthe battery cell 116 to electrically insulate the battery cell 116 fromthe electrically conductive internal heat fin 112. It may be appreciatedthat, for embodiments in which the internal heat fin 112 is notelectrically conductive, the electrically insulating polymer layer 120may not be used. In certain embodiments of the battery module 22, theremay be exactly one internal heat fin 112 for each battery cell 116 ofthe battery module. In other embodiments, the battery module 22 mayinclude one extra internal heat fin 112 that is disposed directly on topof the first battery cell assembly 114 (e.g., directly on top of theillustrated PCM layer 124) of the battery module 22. Further, asillustrated, in certain embodiments, the internal heat fin 112 may bemanufactured from a single piece of heat conductive material, which maylimit manufacturing costs, simplify assembly of the battery cellassembly 114, and ensure good heat transfer within the internal heat fin112.

For the embodiment of the battery cell assembly 114 illustrated in FIG.12, the battery cell 116, which is illustrated as a pouch battery cell116, is configured to be sandwiched directly between a top portion 282and a bottom portion 284 of the frame 118. As set forth in detail below,the frame 118 may be coupled to the pouch battery cell 116 in a numberof different ways, including embodiments where the frame 118 may bedisposed within the pouch battery cell 116. Additionally, in certainembodiments, the top portion 282 and the bottom portion 284 of the frame118 may be coupled to one another (e.g., near an end portion 286 or 288)via a hinge element configured to allow the frame 118 to open to receiveand to subsequently close around the pouch battery cell 116. For theembodiment illustrated in FIG. 12, the top portion 282 and the bottomportion 284 of the frame 118 may include mating features (e.g., snaps,hooks, clasps, etc.) that secure the top and bottom portion 282 and 284to one another around the pouch battery cell 116. It may also beappreciated that, as set forth in detail below, the frame 118 mayinclude features (e.g., openings, windows, slots, etc.) to allow the tabelectrodes 129 of the pouch battery cell 116 to extend through the endportions 286 and 288 of the assembled frame 118. Further, when the frame118 is disposed around the pouch battery cell 116, the planar topsurface 300 and the planar bottom surface 302 of the pouch battery cell116 remain exposed to contact or provide a thermal pathway to componentsof the battery cell assembly 114 (e.g., the internal heat fin 112, thethermal gap pad 122, and/or the PCM layer 124) that may be disposedabove and below the pouch battery cell 116 in the stack.

Additionally, the embodiment of the battery cell assembly 114illustrated in FIG. 12 also includes the thermal gap pad 122. For theillustrated embodiment, the thermal gap pad 122 is disposed above thetop portion 282 of the frame 118 and is in direct contact with theexposed planar top surface 300 of the pouch battery cell 116. As setforth above, the thermal gap pad 122 may generally provide a thermalpathway between the planar top surface 300 of the pouch battery cell 116and the PCM layer 124. Furthermore, as set forth above, in certainembodiments, the thermal gap pad 122 may also mitigate manufacturingvariability (e.g., of the pouch battery cell 116 or the PCM layer 124),ensure tight packing of the battery assembly 114, ensure uniformpressure to each pouch battery cell 116, and provide vibrationaldampening to the components of the battery module 22. In otherembodiments, the thermal gap pad 122 may be additionally oralternatively positioned directly between the bottom planar surface 302of the battery cell 116 and the internal heat fin 112 or directlybetween the PCM layer 124 and another internal heat fin 112 (not shown)(e.g., an internal heat fin 112 of the next battery cell assembly in thestack) positioned above the PCM layer 124.

The embodiment of the battery cell assembly 114 illustrated in FIG. 12also includes the PCM layer 124 disposed directly on top of the thermalgap pad 122. It may be appreciated that, in other embodiments, the PCMlayer 124 may be disposed elsewhere in the battery cell assembly 114.For example, in certain embodiments, the PCM layer 124 may be disposedbelow the thermal gap pad 122, directly against the planar top surface300 of the pouch battery cell 116. In other embodiments, the PCM layer124 may be disposed below the pouch battery cell 116, directly againstthe planar bottom surface 302 of the pouch battery cell 116. In stillother embodiments, the battery cell assembly 114 may include more thanone PCM layer 124 (e.g., 2 or 3 or more PCM layers 124) disposed in anycombination of the positions within the battery cell assembly 114discussed herein.

FIG. 13 is a diagram 303 illustrating thermal pathways through thethermal management system of the battery module 22. In particular, FIG.13 illustrates a first thermal pathway 304 and a second thermal pathway305 by which heat generated by the battery cell 116 may be transferredto and dissipated by the heat sink outer wall features (e.g., heat sinkside plates 60 and 62) of the battery module 22. In other words, thefirst and second thermal pathways 304 and 305 represent a number ofcomponents of the battery module 22 that are in thermal contact (e.g.,thermal communication) with one another. As such, each block in thediagram 303 represents a thermal resistance (e.g., a resistance to heatflow) of individual components, as well as combinations of components,along the first and second thermal pathways 304 and 305 for theembodiment of the battery cell assembly 114 illustrated in FIG. 12. Itshould be appreciated that the diagram 303 illustrates a thermalmanagement system of a battery module 22 having only one heat sink sideplate 60 or 62. For embodiments of the battery module 22 having a secondheat sink side plate, as illustrated in FIG. 5, the diagram 303 wouldinclude a second half (e.g., a mirror image of the diagram 303 reflectedacross the line 307) having a third thermal pathway (e.g., a reflectionof the first thermal pathway 304) and a fourth thermal pathway (e.g., areflection of the second thermal pathway 305) to the second heat sinkside plate.

As illustrated in FIG. 13, the block 306 is representative of thebattery cell 116, which may generate heat during operation and may havean associated thermal resistance. As heat is generated by the batterycell 116, at least a portion of the heat may be directed along the firstthermal pathway 304. Accordingly, the heat generated by the internalcomponents of the battery cell 116, which are discussed in greaterdetail below, may traverse an interface that may include one or morelayers (e.g., the electrically insulating polymer layer 120 and thebattery cell packaging discussed below) having a particular combinedthermal resistance, which is illustrated by the block 308. Subsequently,the heat transferred through the interface represented by block 308 mayreach an internal heat fin 112 disposed below the battery cell 116 inthe battery cell assembly 114. Accordingly, block 310 of FIG. 13represents the thermal resistance of the internal heat fin 112 toconduct heat horizontally (e.g., along the X axis 44, toward the heatsink side plates 60 and 62) along the thermal pathway 304. The heatconducted by the internal heat fin 112 may subsequently reach a secondinterface that may include the thermal gap pad 108 of the heat sink sideplate assembly 106, the thermal resistance of which is represented byblock 311. Finally, the heat traversing the thermal gap pad 108 mayreach a heat sink side plate 60 or 62, which may have a thermalresistance that is represented by block 312. Further, in the heat sinkside plate 60 or 62, the first thermal pathway 304 may merge with athermal pathway 313 of the heat sink side plate, which may represent aconvention-driven heat flow across the heat sink side plate 60 or 62(e.g., from bottom to top). It may be appreciated that a total thermalresistance of the first thermal pathway 304 may be represented by a sumof the individual thermal resistances represented by the blocks 306,308, 310, 311, and 312.

Additionally, at least a portion of the heat generated by the batterycell 116 may be directed along the second thermal pathway 305. Forexample, the heat being generated by the internal components of thebattery cell 116 may first traverse a third interface, which has athermal resistance that is represented by block 314, and which mayinclude one or more components or layers of the battery cell assembly114 (e.g., the thermal gap pad layer 122 and the battery cell packagingdiscussed below). The heat that traverses the third interface maysubsequently reach the PCM layer 124, which has a thermal resistancethat is represented by block 316. As discussed in detail below,depending on the temperature at or near the PCM layer 124, the PCM layer124 may conduct a substantial portion of the heat received (e.g.,primarily along the Y axis 42) to the internal heat fin 112 (not shown)disposed above the PCM layer 124. However, it may be appreciated that,as discussed in detail below, once the PCM layer 124 reaches a thresholdtemperature (e.g., a melting point of the phase change element of thePCM layer 124), the PCM layer 124 may instead absorb a substantialportion of the heat received along the thermal pathway 305.

Subsequently, the heat transferred through the PCM layer 124,represented by block 316 of FIG. 13, may reach a second internal heatfin 112 (e.g., an internal heat fin 112 of the next battery cellassembly 114) that is disposed above the PCM layer 124 in the batterycell assembly 114. Block 318 represents the thermal resistance of thisinternal heat fin 112 to conduct heat horizontally (e.g., along the Xaxis 44, toward the heat sink side plates 60 or 62) along the secondthermal pathway 305. The heat conducted by the internal heat fin 112 maysubsequently reach the second interface (e.g., including the thermal gappad 108 of the heat sink side plate assembly 106) having the thermalresistance represented by block 311. Finally, the heat traversing thethermal gap pad 108 may reach a heat sink side plate 60 or 62, havingthe thermal resistance represented by block 312. Further, in the heatsink side plate 60 or 62, the second thermal pathway 305 may merge withthe aforementioned thermal pathway 313 of the heat sink side plate 60 or62. It may be appreciated that a total thermal resistance of the secondthermal pathway 305 may be represented by a sum of the individualthermal resistances represented by the blocks 306, 314, 316, 318, 311,and 312. Further, it may be appreciated that, a temperature 317 of thebattery cell 116 and a temperature 319 of the heat sink side plate 60 or62 may be managed or controlled by the thermal resistances of thevarious layers and components of the battery assembly 114, asillustrated by FIG. 13.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful in the manufacture ofbattery modules and battery systems. Presently disclosed are embodimentsincluding a thermal management system having passive or active coolingfeatures. For example, the disclosed battery cell assembly embodimentsmay include a one-piece internal heat fin, a thermal gap pad, and a PCMlayer that may work in conjunction with heat sink outer wall features(e.g., heat sink side plates that may include fans or liquid coolingblocks) of the battery module housing to regulate the temperature ofeach battery cell of the battery module. Additionally, the disclosedthermal gap pads may ensure efficient thermal transfer between layers ofthe battery cell assemblies and provide a uniform pressure to each ofthe battery cells of the battery module. Further, the PCM layer of eachbattery assembly may provide a more uniform temperature profile for thebattery module in spite of internal or external heating. The technicaleffects and technical problems in the specification are exemplary andare not limiting. It should be noted that the embodiments described inthe specification may have other technical effects and can solve othertechnical problems.

Battery Module with Phase Change Material (PCM) Layer

FIG. 14 is a schematic illustrating an embodiment of the PCM layer 124.It may be appreciated that components of the PCM layer 124 illustratedin FIG. 14 are not drawn to scale but, rather, are disproportionallyenlarged for discussion purposes. The embodiment of the PCM layer 124illustrated in FIG. 14 includes a first packaging layer 320 and a secondpackaging layer 322 with a phase change material (PCM) 324 disposeddirectly in between. In certain embodiments, the first and secondpackaging layers 320 and 322, which may be referred to as the packagingof the PCM layer 124, may be manufactured from a polymer (e.g.,polyvinyl chloride (PVC)) or another suitable electricallynon-conductive material. In other embodiments, the packaging of the PCMlayer 124 may include a single packaging layer disposed on one side ofthe PCM 324 or a pouch completely surrounding the PCM 324. Additionally,in certain embodiments, the illustrated first and second packaginglayers 320 and 322 may be manufactured from different materials, forexample, to provide different thermal properties (e.g., differentthermal resistance) between the first side 326 and the second side 327of the PCM layer 124. In addition to electrical insulation, the firstand second packaging layers 320 and 322 may generally provide structuralsupport to the PCM 324 disposed between the layers to, for example,maintain the integrity of the PCM 324 during assembly of the batterycell assembly 114. Also, in certain embodiments, the PCM 324 may beadhered (e.g., glued or otherwise bonded) to the internal surfaces ofthe first and second packaging layers 320 and 322. Further, theillustrated PCM layer 124 has a generally planar structure (e.g.,generally disposed within or along a X-Z plane defined by the X axis 44and the Z axis 40) having a thickness 321 (e.g., disposed along the Yaxis 42). For example, in certain embodiments, the PCM layer 124 mayhave a thickness 321 less than or equal to approximately 1 millimeters(mm), 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. In otherembodiments, the PCM layer 124 may have a thickness 321 greater than 3mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, for example, to enabletight stacking of the elements of the battery assembly 114 in a tallerbattery module 22.

The PCM 324 of the PCM layer 124 illustrated in FIG. 14 includes asupport material (e.g., layers of highly oriented pyrolytic graphite(HOPG), graphite, or graphene) that is loaded or impregnated with aparaffin-based phase change element. These features are schematicallyillustrated in FIG. 14 by the layers of support material (e.g., theillustrated honeycomb-like support material layers 328) that are loadedwith the paraffin-based phase change elements (e.g., represented by thedashed spheres 330). It may be appreciated that HOPG, graphite, andgraphene are provided as a non-limiting example of a support material ofa PCM layer 124 and that, in other embodiments, other organic orinorganic support materials may additionally or alternatively be used.It may be appreciated that the term “melting point” as used hereinrefers to a wide or narrow range of temperature values (e.g., 50±5° C.or 45° C. to 55° C.) over which the phase transition (e.g., asolid-to-liquid phase transition) of phase change elements 330 occurs.For example, in certain embodiments, the PCM 324 may have a meltingpoint that ranges from approximately 47° C. to approximately 52° C.

With the forgoing in mind, when the PCM 324 is below the melting pointof the phase change element 330, the phase change element 330 may remainin solid form on the support material layers 328. Within thistemperature range, the PCM 324 may mainly conduct heat along least twoaxes through the PCM layer 124, and these axes may be defined by theorientation of the support material layers 328 of the PCM 324. Forexample, the PCM 324 may predominantly or primarily conduct heat along afirst axis (e.g., along the Y axis 42, perpendicular to the first andsecond support layers 320 and 322), may secondarily conduct heat along asecond axis (e.g., along the X axis 44, toward the side portions 50 and52 of the battery module 22), and may generally have poor heatconduction along a third axis (e.g., along the Z axis, toward the endportions 46 and 56 of the battery module 22). For example, in certainembodiments, the PCM layer 124 may conduct between 60% and 98%, between75% and 95%, or between 80% and 90% of the heat along the Y axis 42(e.g., vertically, away from the pouch battery cell 116), and mayconduct all or most the remainder of the heat along the X axis 44. Asillustrated in FIG. 14, this may result from the support material layers328 primarily residing in the X-Y plane (i.e., defined by the Y axis 42and the X axis 44).

If the temperature of the PCM 324 is raised to the melting point of thephase change element 330, the PCM 324 may begin to absorb a substantialportion of the heat being received by the PCM layer 124 to cause thephase change elements 330 to undergo a phase transition, such as asolid-to-liquid phase transition. It should be appreciated that once thephase transition begins, the PCM 324 may generally maintain atemperature at or near the melting point of the phase change element 330until the phase transition is complete (e.g., all of the phase changeelement 330 has transitioned from solid to liquid) and the heat capacityof the PCM 324 is exhausted. After completion of the phase transition,if the other components of the battery assembly 114 cool below themelting point of the phase change element 330, the PCM layer 124 mayundergo a reverse phase change, dissipating the thermal energy releasedby the reverse phase change primarily along the Y axis 42 andsecondarily along the X axis 44. Accordingly, the PCM layer 124 maygenerally militate against temperature fluctuations within the batterymodule 22, providing a more uniform temperature profile within thebattery module 22 despite temperature fluctuations of the battery cells116 and/or the ambient environment outside of the battery module 22.

In an example embodiment, the phase change element 330 of the PCM 324 ofthe PCM layer 124 may have a melting point of approximately 50° C. Forthis example, when the PCM layer 124 is below 50° C., the PCM 324 maygenerally conduct heat (e.g., received from the pouch battery cell 116directly or via the thermal gap pad 122) primarily along the Y axis 42and secondarily along the X axis 44. For this example, when the PCMlayer 124 is initially heated to a temperature near or above 50° C., thePCM 324 may begin to absorb a substantial portion of the heat to affectthe phase transition of the phase change element 330. Throughout thisphase transition, the PCM layer 124 may continue to absorb heat withoutincreasing in temperature due to the thermodynamics of the phasetransition. Accordingly, the PCM layer 124 may substantially maintaintemperatures within the battery module 22 (e.g., near each PCM layer124) at or below the melting point of the phase change element 330 untilthe entire phase change element 330 has completed the solid-to-liquidphase transition. For this example, when the PCM layer 124 continues tobe heated after the phase change element 330 has completed the phasetransition, the PCM 324 may generally discontinue absorbing heat andresume conducting heat along the Y axis 42 and the X axis 44.Furthermore, for this example, when the battery module 22 cools to apoint that one or more layers of the battery assembly 114 in thermalcontact with the phase-changed PCM layer 124 (e.g., the thermal gap pad122, the pouch battery cell 116, and/or the internal heat fin 112) arecooler than approximately 50° C., the phase change element 330 mayundergo the reverse phase transition (e.g., a liquid-to-solid phasetransition), and may deposit the thermal energy generated during thisreverse phase transition into another layer in thermal contact with thePCM layer 124 (e.g., the internal heat fin 112 disposed above the PCMlayer 124 in the battery cell assembly 124). Accordingly, the PCM 324 ofthe PCM layers 124 of the battery module 22 may generally provide a moreuniform temperature profile for the battery module 22 despite internalor external temperature fluctuations. This more uniform temperatureprofile may generally increase the life of the battery module 22,decrease capacity fade and/or power fade for the battery module 22,and/or mitigate thermal runaway of the battery module 22.

FIG. 15 is a cross-sectional schematic of an embodiment of the pouchbattery cell 116 illustrated FIG. 12 taken along line 15-15. In contrastto the embodiment illustrated in FIG. 12, the embodiment illustrated inFIG. 14 includes PCM layers 124A and 124B positioned directly adjacentthe pouch battery cell 116 (e.g., contacting the top planar surface 300and the bottom planar surface 302 of the battery cell 116).Additionally, the PCM layers 124A and 124B may function as set forthabove to conduct heat (e.g., generated by the pouch battery cell 116during operation) primarily along the Y axis 42 and secondarily alongthe X axis 44 at temperatures above and below the melting point of thephase change element 330, and may maintain a temperature at or near themelting point of the phase change element 330 until the phase changeelement 330 has completed the corresponding phase change. It may beappreciated that a battery cell assembly having two PCM layers 124A and124B per pouch battery cell 116, as illustrated in FIG. 15, provides agreater heat capacity per battery cell assembly than using a single PCMlayer 124, as illustrated in FIG. 12. It may be appreciated that, whilethe present discussion may be directed toward lithium ion battery cells,in certain embodiments, the pouch battery cell 114 may be a nickelhydride battery cell, or another suitable electrochemical battery cell.As discussed above, the pouch battery cell 116 illustrated in FIG. 15includes the tab electrodes 129, which include a cathode tab electrode129A and an anode tab electrodes 129B. It should be appreciated that thepresent approach may be applicable to other types of battery cells(e.g., hard case prismatic battery cells) beyond the pouch battery cell116 illustrated in FIG. 15.

The pouch battery cell 116 illustrated in FIG. 15 includes an outerelectrically insulating layer 334 (e.g., a polyimide film or anothersuitable electrically insulating polymer). Additionally, the pouchbattery cell 116 also includes a metallic foil layer 336 (e.g., analuminum foil layer) that may provide enhanced structural integrity, tobe more resilient to pinhole deformities, to provide a better gasbarrier layer, and so forth, compared to the use of insulating polymerfilms alone. Further, the illustrated pouch battery cell 116 includes aninner electrically insulating layer 338 (e.g., a polyimide film oranother suitable electrically insulating polymer) to electricallyisolate the metallic foil layer 336 from the internal components of thepouch battery cell 116. In certain embodiments, the three layers may beindividually applied to the pouch battery cell or may be provided as asingle film including the three layers 334, 336 and 338, which may becollectively referred to as a pouch material film 339. As illustrated inFIG. 15, the pouch material film 339 may be sealed (e.g., sonicallywelded, sealed with epoxy, or another suitable seal) around the tabelectrodes 129 to isolate the internal components of the pouch batterycell 116.

Inside the pouch battery cell 116 illustrated in FIG. 15, the cathodetab electrode 129A may be electrically coupled to one or more cathodelayers 340 while the anode tab electrode 129B may be electricallycoupled to one or more anode layers 342. In certain embodiments, thecathode layers 340 may be made from an aluminum plates that are coatedwith a cathode active material (e.g., including a lithium metal oxidesuch as lithium nickel cobalt manganese oxide (NMC) (e.g., LiNiCoMnO₂),lithium nickel cobalt aluminum oxide (NCA) (e.g., LiNiCoAlO₂), orlithium cobalt oxide (LCO) (e.g., LiCoO₂)). In certain embodiments, theanode layers 342 may be made from copper plates that are coated with ananode active material (e.g., including graphite or graphene). It shouldbe appreciated that these materials are merely provided as examples, andthat the present approach may be applicable to a number of differentlithium ion and nickel metal hydride battery modules.

Further, as illustrated in FIG. 15, the at least one cathode layer 340and the at least one anode layer 342 are interdigitated with oneanother, along with an insulating polymer layer 344 (e.g., a poly-imagefilm or another suitable electrically insulating polymer film) disposedbetween each cathode and anode layer, to form an electrochemical stack346. It should be appreciated that, the illustrated electrochemicalstack 346 is merely provided as an example. In other embodiments, theelectrochemical stack 346 may be implemented as a “jellyroll,” whereinthe cathode tab electrode 129A and the at least one cathode layer 340may be formed from a single, continuous strip of aluminum foil and theanode tab electrode 129B and the at least one anode layer 342 may beformed from a single, continuous strip of copper foil. For such animplementation, the aluminum foil strip and the copper foil strip may bestacked, along with a number of electrically insulating layers, andwound about a mandrel to provide the electrochemical stack 346.

During assembly of the illustrated pouch battery cell 116, theelectrochemical stack 346 may first be formed using a stack of cathodeand anode plates or using a “jellyroll,” as set forth above.Subsequently, the pouch material film 339 may disposed around theelectrochemical stack 346, and the pouch material film 339 may then bepartially sealed to the tab electrodes 129. Then, an electrolyte 347(e.g., including carbonate solvents and LiPF₆ as a salt) may be added tothe electrochemical stack 346 partially sealed pouch material film 339,and the pouch material film 339 may then be completely sealed to the tabelectrodes 129 to provide the pouch battery cell 116.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful in the manufacture ofbattery modules and battery systems. Presently disclosed are batterycell assembly embodiments that include at least one PCM layer that maywork in conjunction with internal heat fins and external heat sink outerwall features (e.g., heat sink side plates that may include fans orliquid cooling blocks) to regulate the temperature of each battery cellof the battery module. The PCM layers of the battery module embodimentspresently disclosed may generally provide a more uniform temperatureprofile for the battery module in spite of internal or external heating,which may enable more uniform power characteristics and improvedlongevity for the battery module. Further, the disclosed PCM layers mayalso enable heat conduction along particular directions (e.g., along thestack of the power assembly and/or toward the heat sink side plates) toenable efficient thermal pathways within the battery module and,thereby, enable passive cooling of the battery module. The technicaleffects and technical problems in the specification are exemplary andare not limiting. It should be noted that the embodiments described inthe specification may have other technical effects and can solve othertechnical problems.

Battery Cell with Integrated Internal Heat Fin

FIG. 16 is a schematic exploded view of an embodiment of a battery cell348 that is integrated with the internal heat fin 112. The internal heatfin 112 may be integrated with the battery cell 348 as one of severallayers that, in addition to other functions, operate to seal in theelectrochemical stack 346 of the battery cell 348. The battery cell 348illustrated in FIG. 16 includes the internal heat fin 112 with thecurved side portions 280. Furthermore, the internal heat fin 112 isessentially an outermost layer of the battery cell 348 such that isremains conductively and otherwise accessible across the entirety of itsoutermost side. The internal heat fin 112 also serves as a base layer ofthe battery cell 348 in that the other components of the battery cell348 are arranged on one side of the internal heat fin 112, including theframe 118, a illustrated in FIGS. 17 and 18.

As illustrated in FIG. 16, an electrically insulating polymer layer 120is disposed against the surface of the internal heat fin 112 toelectrically isolate the internal heat fin 112 from the electrochemicalstack 346. The electrically insulating polymer layer 120 isrepresentative of any of various electrically insulating layers. Forexample, the electrically insulating polymer layer 120 may berepresentative of multiple layers including a thermally conductivepolymer layer, a phase change material layer, a layer includingcombinations of such material, and so forth. In the illustratedembodiment, the insulating polymer layer 120 is layered only on one sideof the internal heat fin 112 and may or may not extend across the entiresurface of the internal heat fin 112. It may be desirable to cover onesurface of the internal heat fin 112 entirely with the polymer layer 120for sealing and insulative purposes with respect to other components ofthe battery cell 348. Furthermore, it may be desirable to leave onesurface of the internal heat fin 112 completely exposed for heattransfer purposes and manufacturing efficiency.

With regard to the functionality of the internal heat fin 112 and theinsulating polymer layer 120, these two layers cooperate to providethermal conductivity without electrical conductivity relative to theelectrochemical stack 346 and provide one side of a sealed engagementabout the electrochemical stack 346. Other layers may engage the polymerlayer 120 and/or internal heat fin 112 about the electrochemical stack346 to provide the second side of the sealed engagement. Indeed, turningto the illustrated embodiment, three layers (e.g., layers 334, 336, and338) may be used to seal the electrochemical stack 346 to the internalheat fin 112 and/or polymer layer 120. As illustrated, the innerelectrically insulating polymer layer 338 (e.g., a polyimide layer oranother suitable electrically insulating polymer) may be disposeddirectly against the electrochemical stack 346 and may electricallyisolate the electrochemical stack 346 from a metallic foil layer 336.Further, an outer electrically insulating polymer layer 334 mayelectrically isolate an outer surface of the metallic foil layer 336. Itshould be appreciated that, in certain embodiments, the three layers334, 336, and 338 may be provided as a single film, which maycollectively be referred to as the pouch material film 339.Additionally, in certain embodiments, the pouch material film 339 mayinclude a phase change material layer (e.g., like the PCM layer 124,discussed above) sandwiched between the electrically insulating polymerlayers 338 and 334.

During construction of the battery cell 348, the electrically insulatingpolymer layer 120 may be stacked or otherwise arranged on top of theinternal heat fin 112. The internal heat fin 112 and the polymer layer120 may have common boundaries or the polymer layer 120 may be smallerin length and width than the internal heat fin 112. For example, in oneembodiment, the polymer layer 120 may be extruded on a portion of theinternal heat fin 112 or extruded completely over one side of theinternal heat fin 112. On top of the electrically insulating polymerlayer 120, the electrochemical stack 346 (e.g., a stack of cathode andanode plates or a “jellyroll”, as set forth above) may be disposed.Then, the pouch material film 339 may be disposed over theelectrochemical stack 346, either as three separate layers 334, 336, and338 or as a single pouch material film 339. The pouch material film 339(e.g., layers 334, 336, and 338) may then be partially sealed around aperimeter of the electrochemical stack 346. That is, in certainembodiments, at least a portion of the pouch material film 339 (e.g.,the layers 334, 336, and 338) may be coupled to the electricallyinsulating polymer layer 120 or directly to the internal heat fin 112around a perimeter of the electrochemical stack 346. In certainembodiments, this coupling may be achieved using sonic welding, anadhesive, or another suitable method of coupling. In certainembodiments, at least a portion of the electrically insulating polymerlayer 120 may be coupled to the internal heat fin using sonic welding,an adhesive, or another suitable method of coupling. Further, in certainembodiments, at least a portion of the pouch material film 339 (e.g.,the layers 334, 336, and 338) may be coupled to the electricallyinsulating polymer layer 120 at the same time as the electricallyinsulating polymer layer 120 is coupled to the internal heat fin 112(e.g., using sonic welding).

It may be appreciated that the battery cell 348 illustrated in FIG. 16enables a reduced thermal barrier (e.g., improved thermal contact orcommunication) between the electrochemical stack 346 of the battery cell348 and the internal heat fin 112 relative to other embodiments withoutan integration of such features. This may be illustrated by pointing toother embodiments of the present disclosure that do not include theinternal heat fin 112 integrated with certain other package components.For example, the embodiment of the battery cell assembly 114 illustratedin FIG. 12 (which includes the embodiment of the pouch battery cell 116illustrated in FIG. 15) has at least three electrically insulatingpolymer layers (e.g., the electrically insulating polymer layers 120,334, and 338) disposed between the electrochemical stack 346 and theinternal heat fin 112. It may be appreciated that, in general, theseelectrically insulating polymer layers 120, 334, and 338 provide atleast a portion of the thermal resistance of the thermal pathway 304(e.g., contributes to the thermal resistance of the first interfacerepresented by block 308 of FIG. 13). Accordingly, it may be appreciatedthat the battery cell 348 illustrated in FIG. 16 includes only a singleinsulating polymer layer 120 disposed between the electrochemical stack346 and the internal heat fin 112. As such, the battery cell 348illustrated in FIG. 16 enables a higher thermal conductivity pathway(e.g., thermal pathway 304 of FIG. 13 having a lower thermal resistanceat block 308) between the electrochemical stack 346 and the internalheat fin 112.

FIG. 17 is a cross-sectional schematic of the assembled battery cell 348taken along line 17-17 of FIG. 16. As set forth above, the battery cell348 illustrated in FIG. 17 may be formed by stacking the electrochemicalstack 346 on top of the electrically insulating polymer layer 120 and atleast partially sealing the pouch material film 339 around a perimeterof the electrochemical stack 346. After at least partially sealing thepouch material film 339, the electrolyte 347 may be added to theelectrochemical stack 346 and the pouch material film 339 may becompletely (e.g., hermetically) sealed around the electrochemical stack346. In certain embodiments, the pouch material film 339 may be coupledto the electrically insulating polymer layer 120, which is in turncoupled to the internal heat fin 112. Further, in certain embodiments,the frame 118 may then be disposed around the sealed electrochemicalstack 346 of the battery cell 348 (e.g., during construction of abattery cell assembly 114). In other embodiments, the internal heat fin112 may include a number of registration features (e.g., like theregistration features 121 of the frame 118 illustrated in FIG. 12) andthe frame 118 may be excluded altogether.

FIG. 18 is a cross-sectional schematic of an assembled battery cell 350including an internal heat fin 112 as an integral component. Like thebattery cell 348 illustrated in FIG. 17, the battery cell 350illustrated in FIG. 18 includes the electrochemical stack 346 stacked ontop of the electrically insulating polymer layer 120, which is stackedor layered on top of the heat fin 112. Additionally, the battery cell350 illustrated in FIG. 18 includes the frame 118 disposed around theelectrochemical stack 346. However, unlike the battery cell 348illustrated in FIG. 17, the frame 118 of the battery cell 350illustrated in FIG. 18 is disposed inside of the pouch material film339. That is, during the manufacture of the battery cell 350, the pouchmaterial film 339 may be disposed over the electrochemical stack 346 andthe frame 118 and may be sealed around the perimeter of the frame 118.After at least partially sealing the pouch material film 339 around theframe 118, the electrolyte 347 may be added to the electrochemical stack346. Further, the pouch material film 339 may cooperate with otherlayers including at least the internal heat fin 112 and the polymerlayer 120 to provide a complete (e.g., hermetical) seal about both theelectrochemical stack 346 and the frame 118. It may be appreciated that,for the illustrated embodiment of the battery cell 350, the frame 118should be manufactured from a material that is robust to (e.g.,substantially non-reactive with) the electrolyte 347 of the battery cell350.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful in the manufacture ofbattery modules and battery systems. Presently disclosed are embodimentsincluding battery cells that have an integrated internal heat fin, whichenables a more efficient thermal pathway between the battery cell andthe heat sink outer wall features (e.g., heat sink side plates that mayinclude fans or liquid cooling blocks) that are also in thermalcommunication with the internal heat fin. Present embodiments may alsoprovide for efficient manufacture of related battery modules byintegrating certain functions into a single package. The disclosedbattery cell embodiments include an electrochemical stack that ishermetically sealed to the surface of an internal heat fin using a pouchmaterial film. In certain embodiments, the battery cell may include aframe disposed under the pouch material film along with theelectrochemical stack. In certain embodiments, the frame may be disposedoutside of the pouch material film, or may not be used at all. Thetechnical effects and technical problems in the specification areexemplary and are not limiting. It should be noted that the embodimentsdescribed in the specification may have other technical effects and cansolve other technical problems.

System and Method for Encasing a Battery Cell

Turning now to FIG. 19, an embodiment of the battery module 22 isillustrated having thermal interfaces 352 between the battery cells 116,which are arranged in a stacked orientation. The battery cells 116 areshown in a horizontally stacked orientation (e.g., “pancake stack”), butin other embodiments, they may be in a vertically stacked orientation(e.g., “book stack”). The thermal interfaces 352, which may include airgaps and/or heat transfer material, may facilitate passage of a fluidflow (e.g., air flow) between neighboring battery cells 116, which mayhelp diffuse heat produced by the individual battery cells 116 of thebattery module 22. In the embodiment shown, each battery cell 116 isdisposed in a corresponding one of the polymer frames 118, and eachpolymer frame 118 is spaced apart a distance from the adjacent polymerframe 118 using cooperating features of the polymer frames 118 to allowthe thermal interfaces 352. In certain embodiments, an external coolingfeature, such as a fan (not shown), may be included in the batterysystem 20, such that fluid flow may be passed through the thermalinterfaces 352 formed between the adjacent battery cells 116 in thebattery module 22. Such an external cooling feature may improve thethermal management of the battery module 22, thereby increasing its lifespan and efficiency.

In some embodiments, such as that shown in FIG. 20, a housing 354 of thebattery module 22 may include one or more forced cooling vents 356. Theforced cooling vents 356 may allow an external cooling feature (e.g.,fan) to pass a flow of coolant, such as air, into the battery module 22so that the coolant may flow through the thermal interfaces 352 betweenthe battery cells 116. In the illustrated embodiment, the forced coolingvent 356 is obround with two parallel sides and two semicircular ends.Further, the forced cooling vent 356 extends out from the housing 354 tofacilitate coupling with an external cooling feature and/or guidance offluid flow. However, it should be understood that, in accordance withpresent embodiments, the forced cooling vents 356 may have any suitableshape, dimension, or location on the housing 354 of the battery module22.

To create the thermal interfaces 352 and to improve fluid flow betweenadjacent battery cells 116, each battery cell 116 may be disposed insidea cell casing or battery cell casing 358, as shown in FIG. 21. Incertain embodiments, two or more battery cells 116 may be disposed in asingle cell casing 358. The cell casings 358 may be separate from thepolymer frames 118 or represent versions of the polymer frames 118. Thatis, the cell casings 358 may function as the polymer frames 118 or maycooperate with separate polymer frames 118 of the battery module 22.

A plurality of cell casings 358, such as that shown in FIG. 21, may bearranged in a stacked orientation within the battery module 22. Eachcell casing 358 may include a first side 360 and a second side 362,which may be coupled to each other by one or more locking features 364and/or via a hinge, as shown in FIG. 24. One or more thermal transferfeatures 366 may extend from the first side 360, the second side 362, orboth the first side 360 and the second side 362. The one or more thermaltransfer features 366 may be configured to facilitate transfer of heatout of the cell casing 358 and away from the corresponding battery cell116 disposed within the cell casing 358. In some embodiments, highlyconductive features may be included in one or more of the thermaltransfer features 366. For example, while an outer surface of the cellcasing 358 may be formed from a polymer, a highly conductive material,such as a metal, may be imbedded into one or more of the thermaltransfer features 366 to increase the heat distribution capacity of thethermal transfer features 366. It should be understood that in someembodiments, some cell casings 358 may not include thermal transferfeatures 366, or may only include thermal transfer features 366 on oneside of the cell casing 358. The plurality of cell casings 358 may bedisposed within the housing 354 or the plurality of cell casings 358 mayat least partially define the housing 354 of the battery module 22. Thecell casings 358 may generally maintain their shape under pressure,which may buttress the structural integrity of the entire battery module22 and/or facilitate distribution of pressure throughout the batterymodule 22 (including pressures associated with operation of the batterycells 116).

The first side 360 and the second side 362 of each of the plurality ofcell casings 358 may include one or more of the thermal transferfeatures 366. The thermal transfer features 366 may be sized and shapedto facilitate efficient transfer of heat away from the cell casing 358to a surrounding environment. Indeed, the thermal transfer features 366may have geometries that expose a large amount of surface area forpurposes of heat transfer. As an example, the thermal transfer features366 of FIG. 21 may include generally circular walls extending from asurface of the cell casing 358. In some embodiments, different shapes(e.g., a ridge, or a circular wall with a passage through the wall) maybe utilized to provide more surface area that is accessible to fluidflowing around the cell casing 358. In some embodiments, the thermaltransfer features 366 may include recesses or concavities (e.g.,dimples) into one or more surfaces of the cell casings 358. Further, thethermal transfer features 366 may be made of a material that differsfrom that of an associated cell casing 358 to increase or otherwisecontrol heat transfer properties. Additionally, the thermal transferfeatures 366 may be arranged with respect to one another to encouragefluid flow in particular directions and/or distribute areas of high heattransfer to certain portions of the surface of the cell casings 358.

The one or more thermal transfer features 366 may include one or morestandoffs 368 that function to distance the associated cell casing 358from other portions of the battery module 22 (e.g., other cell casings358). Specifically, one set of standoffs 368 may engage with another setof standoffs 368 to separate corresponding cell casings 358. The thermaltransfer features 366 illustrated in FIG. 21 are also examples ofstandoffs 368. The standoffs 368 may cooperate with neighboring cellcasings 358 to facilitate fluid flow between neighboring cell casings358 of the plurality of cell casings 358 by providing a space (e.g., thethermal interface 352) between the cell casings 358. The thermalinterface 352 may enable a fluid, such as air, to flow between the cellcasings 358. The fluid flow may improve the thermal management of thebattery module 22 by removing heat produced by the plurality of batterycells 116 and carrying it out of the battery module 22. The standoffs368 may be generally circular (as shown in FIG. 21), or they may besquare, rectangular, triangular, polygonal, or any other suitable shape.While 19 standoffs 368 are shown on the cell casing 358 in FIG. 21, anynumber of standoffs 368 may be included. For example, each cell casing358 may include between about 1 and 200 standoffs 368, 1 and 100standoffs 368, 1 and 50 standoffs 368, 1 and 25 standoffs 368, or anysuitable number.

The thermal transfer features 366 or the standoffs 368 may be arrangedin any manner, including one or more rows and/or columns, or the thermaltransfer features 366 may be disposed only in the middle, edges,corners, etc. of the cell casing 358. It is understood that any suitablearrangement may be used. As briefly noted above, in certain embodiments,it may be desirable to arrange the thermal transfer features 366 suchthat a pathway formed between or by the thermal transfer features 366for fluid flow facilitates the passage of consistent or controlledlevels of fluid flow over the surface area of the cell casing 358. Forexample, in embodiments of the battery module 22 having a greater volumeof available airflow, a relatively large number of thermal transferfeatures 366 may be used to guide the airflow in a circuitous route overthe surface of the cell casing 358 and/or interact with (e.g., transferheat to) the airflow. This may also be achieved by utilizing one or morecomplexly shaped thermal transfer features (e.g., a maze-like wall). Inembodiments having less available airflow, relatively fewer thermaltransfer features 366 may be used to facilitate passage of the limitedairflow over the surface of the cell casing 358. The thermal transferfeatures 366 or standoffs 368 may be solid, or they may be generallyhollow, as shown, to reduce the associated mass of the thermal transferfeatures 366. As noted above, certain geometric configurations of thethermal transfer features 36 may improve the thermal management of thebattery cell 116 by enabling faster heat transfer between the batterycell 116, the cell casing 358, and the coolant flowing past the cellcasing 358.

The standoffs 368 may also improve pressure distribution across eachbattery cell 116 and/or across an assembly of battery cells 116 as awhole. In some embodiments, such as when the battery cells 116 arearranged in a horizontally stacked orientation, a particular standoff368 may improve the distribution of pressure exerted on a correspondingbattery cell 116 by adjacent battery cells 116. Since the battery cells116 are arranged in a stacked manner, each battery cell 116 mayexperience some amount of pressure, such as from battery cells 116disposed above or on top of it. The standoffs 368 may help distributethis pressure by spreading the pressure across a large surface area onthe cell casing 358, such as by using a large number of standoffs 368 onthe first and/or second sides 360 and 362. In other embodiments, thestandoffs 368 may be arranged to transfer the pressure to the strongestpart of the cell casing 358, such as the edges of each side 360 and 362.As described in more detail in FIG. 23, the standoffs 368 on the firstside 360 of a first cell casing 358 may generally align with thestandoffs 368 on the second side 362 of an adjacent second cell casing358.

In certain other embodiments, the thermal transfer feature 366 on thecell casing 358 may include one or more ridges 370, as shown in FIG. 22.The ridges 370 may extend out from the cell casing 358, and may beemployed along with the standoffs 368 or other thermal transfer features366. Each ridge 370 may extend (linearly or circuitously) along a lengthof the cell casing 358, and may enable fluid to flow in between adjacentcall casings 358 by providing one or more fluid pathways. In addition,the ridge 370 on one cell casing 358 may be configured to align and/orinteract (e.g., couple) with the ridge 370 on an adjacent cell casing358. For example, adjacent ridges 370 may be configured to align andmate with each other to improve the alignment and orientation of theadjacent cell casings 358. Indeed, the ridge 370 may include a groove orrecess along the outer surface or distal end that is configured toreceive the outer end of another ridge 370.

The ridge 370, shown as defining a zigzag pattern across the first side360 of the battery cell casing 358 in FIG. 22, may have any design andcontour desired for distributing fluid flow and/or facilitating heattransfer. Any number of ridges 370 may be included on the first and/orsecond sides 360, 362 of the cell casing 358. Depending on systemrequirements and parameters (e.g., the volume of available airflow), theridges 370 may be straight, curved, or may take any other desired formor shape, and they may take direct or indirect paths from a first end372 to a second end 374 of the cell casing 358. For example, inembodiments having a large amount of available airflow, the ridge 370may provide a more circuitous fluid pathway from the first end 372 tothe second end 374. Alternately, in embodiments with a small amount ofavailable airflow, the ridge 370 may provide a more direct fluid pathwayto ensure that the air passes from the first end 372 to the second end374.

As with the standoffs 368 described in FIG. 21, features or aspects ofthe ridge(s) 370 on the first side 360 of one cell casing 358 maygenerally align with features of aspects of the ridge(s) on the secondside 362 of another cell casing 358. Aligning the features of the ridges370 may facilitate alignment of cell casings 358 and/or allow more airto flow between the cell casings 358, thereby improving assemblyefficiency and the thermal management of the battery module 22. Incertain embodiments, such as embodiments with limited airflowavailability in the battery module 22, the cell casing 358 may include acombination of standoffs 368 and ridges 370, such that more airflow maypass between neighboring (e.g., adjacent) cell casings 358.

FIG. 23 shows a cross-sectional view of a first standoff 376 on thefirst side 360, and a second standoff 378 on the second side 362 ofadjacent cell casings 358, where the first and second standoffs 376 and378 are configured to mate, or interlock, with each other. As notedabove, some or all of the corresponding standoffs 368 on adjacent cellcasings 358 may be configured to align and mate with one another. Bymating together, the standoffs 368 may cooperate to facilitateregistration and/or orientation of two or more of the plurality of cellcasings 358 with respect to one another. Any interlocking method may beused to mate the first standoff 376 with the second standoff 378.

In the embodiment shown in FIG. 23, the first standoff 376 includes aprotrusion 380 and an indentation 382. The second standoff 378 includesa corresponding protrusion 380 and indentation 382, which are configuredto interlock with those on the first standoff 376. That is, theprotrusions 380 and indentations 382 of the respective first standoff376 and second standoff 378 are complementary. Each protrusion 380 mayfit into the corresponding indentation 382, such that the first andsecond standoffs 376 and 378 are coupled together. Coupling thestandoffs 368 in this way may prevent the two cell casings 358 fromsliding across one another (e.g., decking). In this way, the standoffs368 may reduce battery cell 116 installation time by making it easierfor a technician to orient and align the battery cells 22, and mayprevent decking of the battery cells 116.

The heights of the first and second standoffs 376 and 378 may determinethe width of the thermal interface 352 between two adjacent casings 358.In the embodiment shown, a first height 384 of the first standoff and asecond height 386 of the second standoff 378 are generally the same, butin other embodiments, the heights 384 and 386 may be different. Theheights 384 and 386 of the standoffs 376 and 378 may be limited by thenumber of battery cells 116 and the size of the battery module 22 basedon overall battery system size limitations. As noted above, differentmating configurations may be utilized, including configurations thatdefine holes through coupled standoffs 368 to facilitate additionalfluid flow therethrough.

FIG. 24 shows the first and second sides 360 and 362 of the cell casing358 coupled to each other with a hinge 388. The hinge 388 may allow thetwo sides 360 and 362 to be more easily closed about the battery cell116. The battery cell 116 may be placed onto the second side 362 of thecell casing 358, and the first side 360 of the cell casing 358 may befolded over the battery cell 116 and into engagement with the secondside 362. The first and second sides 360 and 362 may be contoured toreceive the battery cell 116, and may include openings 390 for the tabelectrodes 129. Locking features 364 may allow the first and secondsides 360 and 362 to snap or otherwise lock together to secure thebattery cell 116 inside the cell casing 358.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful in the manufacture ofbattery cells and battery cell casings. For example, certain embodimentsof the present approach may enable improved thermal management of thebattery cells 116, improve pressure distribution between the batterycells 116, and may reduce the time required for a technician to installor service the battery cells 116 of the battery module 22. By specificexample, including thermal transfer features 366, such as standoffs 368or ridges 370, on battery cell casings 358 may allow coolant to flowbetween adjacent cell casings 358, thereby cooling the battery cells116. The technical effects and technical problems in the specificationare exemplary and are not limiting. It should be noted that theembodiments described in the specification may have other technicaleffects and can solve other technical problems.

System and Method for Sealing a Battery Cell

Turning now to FIG. 25, an exploded view of the battery cell 116 isillustrated having a first layer 400 of pouch material, active material402, the frame 118, and a second layer 404 of pouch material. The activematerial 402 may include two types of active material 402 disposed inalternating layers to form a generally planar electrochemical cell. Thepouch material layers 400 and 404 may each be constructed of one or moresub-layers of material. These sub-layers may include films or foils madeof conductive and non-conductive materials such as polypropylene,aluminum, and/or any other suitable materials. In certain embodiments,the conductive material (e.g., aluminum) may provide limitedpermeability characteristics to the pouch material layers 400 and/or 404to prevent leakage therethrough, and the non-conductive material (e.g.,polypropylene) may be used to electrically insulate the conductivematerial. Certain sub-layers of the pouch material layers 400 or 404 maybe coextruded, bonded, or otherwise coupled together. As a specificexample, an aluminum foil and a polypropylene layer may beultrasonically bonded, or otherwise coupled to each other, to form atleast portions of the upper and lower layers 400 and 404 of pouchmaterial.

The frame 118 includes a plurality of edges that form an opening andsurround side surfaces of the active material 402. The frame 118 mayserve to protect the layers of active material 402 from being crushed orotherwise damaged during operation or handling (e.g., duringinstallation or repair) of the battery cell 116 or related components ofthe battery system 20. For example, the frame 118 may help protect theactive material 402 from external pressures or undesirable contact. Incertain embodiments, the frame 118 may be thicker than the activematerial 402 residing in it, such that the active material 402 isrecessed in the frame 118.

The battery cell 116 may include a number of openings 406 configured toenable bolts, screws, or other coupling mechanisms to secure the batterycell 116 to other battery cells 116 and/or other features of the batterymodule (e.g., the housing 354). The openings 406 may facilitatealignment of two or more battery cells 116 while also securing thebattery cells 116. The openings 406 may extend through any portion(s) ofthe frame 118. For example, the openings 406 may extend through some orall of the corners of the frame 118. In other embodiments, the openings406 may extend through a middle portion or body 408 of the battery cell116. This may be achieved in part by including a hole through the activematerial 402 and sealing the first and second pouch material layers 402and 404 together about the inner edges of the hole in the activematerial 402. Any number of openings 406 may be included in the frame118 and/or through other areas of the battery cell 116, such as themiddle portion 408. The openings 406 also represent any of various typesof coupling features that may be utilized for coupling, registration, ororientation of the frame 118 with respect to other components.

The battery cell 116 may have electrodes extending from it, such aselectrode tabs 129. The electrode tabs 129 are shown extending fromopposite ends of the battery cell 116, but it should be understood thatthe electrode tabs 129 are not opposite each other in other embodiments.Indeed, in some embodiments the electrode tabs 129 may be angledrelative to each other, the electrode tabs 129 may extend from adjacentsides of the battery cell 116, or the electrode tabs 129 may extend froma single side of the battery cell 116. Furthermore, it should be notedthat the electrode tabs 129 are general examples of electrodes, whichmay include geometric characteristics other than flat tabs. Thus,present embodiments may include electrodes with various differentgeometric characteristics (including but not limited to flat tabs) inplace of the electrode tabs 129.

In the illustrated embodiment, the electrode tabs 129 are configured toextend beyond the frame 118. This facilitates communicative orelectrical coupling of other features (e.g., other battery cells 116)with the battery cell 116 via the electrode tabs 129. This also involvessealing about portions of the electrode tabs 129 to avoid leakageissues. This sealing with respect to the electrode tabs (or other typesof electrodes) may be facilitated by lip areas 409, which may includeextended portions of boundaries of the first and second layers 400 and404 of pouch material. In the illustrated embodiment, the lip areas 409of the second pouch material layer 404 are conformed toward thecorresponding electrode tabs 129 to facilitate a sealable engagementwith the electrode tabs 129. Further, the lip areas 409 extend beyondthe corresponding electrode tabs 129 to facilitate sealed engagementwith not only the electrode tabs 129 but also other features (e.g., theopposing lip areas 409 and/or the frame 118). In some embodiments, bothsets of lip areas 409 are conformed for engagement. Further, in someembodiments, the lip areas 409 may be in different locations along thecorresponding first and second pouch material layers 400 and 404.

The active material 402 includes an upper surface 410, a lower surface412, and side surfaces 414. The active material 402 may be disposed inan opening of the frame 118. In other words, the frame 118 may bearranged around the active material 402 such that edges 416 of the frame118 surround the side surfaces 414 of the active material 402. Thus,when the first layer 404 of pouch material and the second layer 400 ofpouch material are positioned on either side of the opening formed bythe frame 118 and sealed about the frame 118 (including embodimentswherein surfaces of the frame 118 and/or the electrode tabs 129 aredirectly sealed to the pouch material layers 400 and 404), the activematerial 402 is sealed in the battery cell 116. As discussed above, theelectrode tabs 129 may extend outside of this sealed area and facilitateelectrical access to the active material 402.

FIGS. 26-31 include partial cross-sectional views that schematicallyillustrate a number of different ways the layers 400 and 404 of pouchmaterial may seal about the frame 118 and active material 402. It shouldbe noted that FIGS. 26-31 generally represent cross-sectional viewstaken along a length of the battery cell 116 that does not include anelectrode extending therethrough. For example, with reference to thebattery cell 116 illustrated in FIG. 25, a partial cross-sectional viewwith similar characteristics would be taken lengthwise from the middleof the battery cell 116. Thus, electrodes such as the electrode tabs 129are not visible in the cross-sectional views of FIGS. 26-31. It shouldbe noted that different portions of the battery cell 116, such asdifferent edges of the frame 118, may incorporate different structuralfeatures such as those illustrated in FIGS. 26-31. For example, a lengthof the battery cell 116 may incorporate one type of cross-section whilea width may incorporate a different type of cross-section.

Turning first to FIG. 26, the second (or upper) layer 404 of pouchmaterial is disposed over the upper surface 410 of the active material402 and an upper surface 418 of the frame 118. Specifically, in theillustrated embodiment, the second layer 404 of pouch material iscoupled or sealed against the upper surface 418 of the frame 118.Similarly, the first (or lower) layer 400 of pouch material is disposedunder the lower surface 412 of the active material 402 and a lowersurface 420 of the frame 118, and the first layer 400 of pouch materialis sealed against the lower surface 412. The side surface 414 of theactive material 402 wall may be generally flat, and may be essentiallyflush with a generally flat inner surface of the edge 416 of the frame118, thereby reducing the amount space between the active material 402and the frame 118 inside the battery cell 116. By arranging andcoordinating the features of the battery cell 116 in the mannerillustrated in FIG. 26, the first and second layers 400 and 404 of pouchmaterial cooperate with the frame 118 to provide a seal with respect tothe active material 402. In embodiments such as that illustrated in FIG.26, the frame 118 is an active component for sealing in the activematerial 402. In other words, there is no pouch material layer betweenthe frame 118 and the active material 402.

To create the seal in FIG. 26, the second layer 404 of pouch material issealed to the upper surface 418 of the frame 118, and the first layer400 of pouch material is sealed to the lower surface 420 of the frame118. The first and second layers 400 and 404 of pouch material may besealed to the surfaces 418 and 420 using a heat seal. Alternately, anadhesive, such as glue, high bond tape, dispensed adhesive, pumpableadhesive, an ultraviolet light curable bond, etc., may be used. Incertain embodiments, an adhesive may be applied to an inner surface 421of the layers 400 and 404, enabling the layers 400 and 404 to adhere tothe portions of the battery cell 116 that the layers 400 and 406 extendacross. In some embodiments, a sub-layer of the first and second layers400 and 404 adjacent the frame 118 may include a composition similar tothat of the frame 118 to facilitate a strong engagement with the frame118 via melding of the sub-layers with the frame 118.

In some embodiments, the first and second layers 400 and 404 of pouchmaterial may be trimmed or cut to fit the edges 416 of the frame 118,leading to one or more unsealed edges 422 that expose the inner layersof the first and/or second layers 400 and 404 of pouch material. Asdescribed above, the pouch material may include several sub-layers ofmaterial, including one or more layers, such as aluminum foil, that maybe conductive. In certain embodiments, the unsealed edges 422 may besealed or otherwise covered to reduce or eliminate the exposure of theconductive inner layers of the pouch material in the battery module 22.For example, the exposed edges 422 of pouch material may be covered withhigh bond tape, dispensed adhesive, etc., or the frame may include a lipto cover the exposed edge 422.

While FIG. 26 illustrates the first and second layers 400 and 404coupled to the frame 118, the first and second layers 400 and 404 ofpouch material may also be sealed to each other outside the frame, forexample by a heat seal, as shown in FIG. 27. In certain embodiments,sealing the first and second layers 404 and 400 of the pouch material toeach other outside of the frame 118 may cooperate with sealed engagementbetween the frame 118 and the layers 400 and 404 to provide a morerobust seal around the active material 402. However, in someembodiments, the first and second layers 400 and 404 may be sealedtogether along the outer perimeter of the frame 118 without sealingdirectly to the frame 118. This may efficiently seal the active material402 within the battery cell 116 and provide sufficient structuralsupport from the frame 118 without requiring a sealed coupling betweenthe frame 118 and the first and second layers 400 and 404.

FIGS. 28-30 illustrate embodiments of the battery cell 116 having whatmay be referred to as a grooved seal 424. As shown in FIG. 28, the firstand second layers 400 and 404 of the pouch material may extend acrossthe respective lower and upper surfaces 412 and 410 of the activematerial 402, as described in FIGS. 26-27. Further, the first and secondlayers 400 and 404 may also couple with the respective surfaces 420 and418 of the frame 118. However, unlike the embodiments of FIGS. 26-27,the first and second layers 400 and 404 of the pouch material are alsosealed to each other inside the frame 118. This combination of sealsprovides the grooved seal 424, which may enable a more comprehensiveseal by providing larger inner surfaces 421 of the first and secondpouch material layers 400 and 404 that may be sealed together or to theframe 118.

As illustrated in FIG. 28, when the frame 118 has a substantially squarecross-section and is utilized with the grooved seal 424, a gap may beformed between an inner sidewall or inner edge 426 of the frame 118 andthe grooved seal 424. Such a gap may trap air within the battery cell116. To limit the potential amount of air sealed inside the battery cell116, the frame 118 may be beveled along an inner edge 426 such that theinner edge 426 at least partially follows the contours of the groovedseal 424. For example, in FIG. 29, the inner edge 426 is partiallyangled to follow the contours of the first and second layers 400 and 404of pouch material as they seal to each other inside the frame 118. Whilereducing the amount of air sealed inside the battery cell 116, anglingthe inner edge 426 of the frame 118 may also provide a larger surfacearea of the frame for sealing against the first and second layers 400and 404 of pouch material. For example, a heat seal may be formed on, oran adhesive may be applied to the angled portion of the inner edge 426as well as on the surfaces 418 and 420, allowing a more robust seal. Itshould be noted that different types of beveling of the inner edge 426may be utilized in accordance with present embodiments. For example, inFIG. 30, the inner edge 426 is angled as in FIG. 29, but the inner edge426 extends to a point 428, such that the amount of air sealed insidethe battery cell 116 may be further reduced or eliminated. It shouldalso be noted that the active material 402 may be similarly arranged tofollow the contours of the grooved seal 424 and thus limit gap spacebetween the grooved seal 424 and the active material 402.

In another embodiment, shown in FIG. 31, the first and second layers 400and 404 of pouch material are sealed to each other, and also sealed tothe frame 118. However, rather than sealing to outer sides 418 and 420of the edge 416, the first and second layers 400 and 404 of pouchmaterial are sealed inside the edge 416 of the frame 118. Sealing thefirst and second layers 400 and 404 of pouch material inside the edge416 of the frame 118 may reduce or prevent exposure of unsealed edges422 of the pouch material, as well as enabling a double seal, in whichthe sealed first and second layers 400 and 404 of pouch material aresealed to each other, and are further sealed inside the frame 118. Withregard to covering exposed edges of the first and second layers 400 and404 of pouch material, while not illustrated in FIGS. 26-30, it shouldbe noted that coatings, layers, tapes, and the like may be utilized tocover the exposed edges to prevent potential communicative contact withany conductive sub-layers of the first and second layers 400 and 404 ofpouch material.

In embodiments having a beveled or angled inner wall 426, as in FIGS.29-30, a tool 430 such as that shown in FIG. 32 may be employed to pressthe first and second layers 400 and 404 of pouch material against theframe 118. The tool 430 may have an angled edge 432 that corresponds tothe angle of the beveled inner edge 426 of the frame 118, allowing thecontours of the tool 430 to match the contours of the grooved seal 424.The tool 430 may enable the pouch material to be pressed closely to theframe 118, thereby improving the quality of contact between the frame118, the first and/or second layers 400 and 404, and the adhesive whichmay be applied between them. In some embodiments, two tools 430 may beused, such that one tool 430 may press on the first layer of pouchmaterial 400 and another tool may press on the second layer 404 of pouchmaterial, causing the first and second layers 400 and 406 of pouchmaterial to seal to each other and to the respective portions of theframe 118. In embodiments wherein the active material 402 is alsobeveled, the tool 430 may include a pair of the angled edges 432.

As noted above, it should be understood that the views of the batterycell 116 shown in FIGS. 26-32 are along edges 416 of the battery cell116 that do not include electrodes (e.g., electrode tabs 129); however,the techniques illustrated therein may be generally applied to edges 416that do include the electrodes. FIG. 33 shows a partially explodedschematic of a cross sectional view of the battery cell 116, having theactive material 402, the first and second layers 400 and 404 of pouchmaterial, the frame 118, and the electrode tab 129. In this embodiment,the electrode tab 129 extends through an opening 433 in the frame 118 toprotrude from the battery cell 116. As noted above, the electrodes maytake any geometric form, and are not limited to the tab embodiment shownherein. To enable the electrode tabs 129 to extend beyond the frame 118,the frame may include one or more openings 433 (e.g., grooves or holes),as shown in FIGS. 34-35, to receive the electrode tabs 129.

FIG. 34 illustrates an embodiment of the frame 118 having grooves 434along the upper surface 418, that are configured to receive theelectrode tabs 129. It should be understood that the grooves 434 may bebeveled, curved, etc., and they may be placed on any portion of theframe 118, including the upper surface 418, the lower surface 420, orany other suitable location. In certain embodiments, one groove may beplaced in the upper surface 418, and another groove may be placed on thelower surface 420. The grooves 434 may enable the active material 402 tobe disposed in the frame 118 such that the electrode tabs 129 align withand extend through the grooves 434. To seal around the electrode tab129, a seal, such as a plastic seal, may be molded into the electrodetab 129 and/or the frame 118. In other embodiments, the electrode tab129 may be vibration welded to the frame 118 or the electrode tab 129may be imbedded in and/or integral with the frame 118. Any method ortechnique may be used to seal the electrode tab 129 to the frame 118. Asdiscussed above, separately or in addition to being sealed with theframe 118, the electrode tabs 129 may be sealed with the first andsecond layers 400 and 404 of pouch material.

In other embodiments, such as that shown in FIG. 35, the frame includesholes 436 for the electrodes (e.g., the electrode tabs 129). Theelectrode tabs 129 may be fed through the holes 436, enabling theelectrode tabs 129 to protrude from the battery cell 116. As in theembodiment having the grooves 434, the electrode tab 129 may be sealedto the frame 118 using a molded plastic seal, melting of the electrodetab 129 to the frame 118, vibration welding, molding the electrode tab129 into the frame 118, etc. Furthermore, separately or in addition tobeing sealed with the frame 118, the electrode tabs 129 may be sealedwith the first and second layers 400 and 404 of pouch material.

FIG. 36 illustrates an embodiment of the frame 118 having a supportfeature 438 across a middle portion 440 of the frame 118. The supportfeature 438 may buttress a middle portion of the active material 402,thereby preventing the active material 402 from sagging or otherwiseextending beyond the contours of the frame 118. It should be understoodthat the support feature 438 may extend in any direction across theframe 118, and may include any of various geometries. For example, thesupport feature 438 may include a grid extending from one side of theframe 118 to another or cantilevered portions (e.g., semicircles thatextend from the inner edges 426 of the frame 118 to support the activematerial 402). This may allow for active material 402 to be placedwithin an opening formed by the frame 118 without allowing the activematerial 402 to pass through the frame 118. As shown, the frame 118 mayalso comprise a pouch groove 442, which provides more surface area forcoupling with the first and second layers 400 and 404 of pouch material.The pouch groove 442 may improve the seal between the frame 118 and thefirst and second layers 400 and 404 by providing more surface area forfirst and second layers 400 and 404 to adhere with, by recessing theseal, and by providing different directional components for theengagement between the first and second layers 400 and 404 and the frame118. Thus, the pouch groove 442 may contribute to a more robust batterycell 116.

FIG. 37 is a schematic representation of a sheet of frame sections 443arranged for assembly of multiple battery cells 116 via a method ofmanufacturing in accordance with an embodiment of the present approach.The sheet of frame sections 443 includes a ladder-like framework with aplurality of openings 444 in which the active material 402 may bedisposed. The edges of the sheet of frame sections 443 may begeometrically configured in a fashion similar or identical to any of thepreviously disclosed embodiments. Indeed, the sheet of frame sections443 may eventually be divided into separate frames 118 for use inproviding a plurality of separate battery cells 116. However, tofacilitate efficient manufacturing, the sheet of frame sections 443 mayinitially be processed as a unit to establish at least certain aspectsof the battery cells 116 before being separated.

FIG. 38 is a block diagram of a method 500 of assembling one or morebattery cells in accordance with an embodiment of the present approach.The method 500 begins with disposing (block 502) the frame 118 on thefirst layer 400 of pouch material. As described above, the frame 118includes the edges 416 coupled (e.g., formed) together to form one ormore openings 444 that may be configured to receive the active material402. In one embodiment, the frame 118 may include the sheet of framesections 443. Next, the active material 402 is disposed (block 504) onthe first layer 400 of pouch material and in the opening(s) 444. Thismay include positioning the tab electrodes 129 such that they extendbeyond the frame 118 or engage a conductive feature integral with theframe 118. The second layer 404 of pouch material is disposed (block506) over the frame 118 and the active material 402. Alternatively, inother embodiments, the active material 402 may be placed on the firstlayer 400 of pouch material before the frame 118, and then the frame 118may be placed about the active material 402. A seal is then established(block 508) involving the first and second layers 400 and 404 of pouchmaterial about the active material 402 and the frame 118. Theestablished seal may include any seal configuration described above(e.g., the groove seal 424). As described above, the first and secondlayers 400 and 404 of pouch material may be sealed to the frame 118, thetab electrodes 129, and/or each other (e.g., inside, around, or withinthe inner perimeter of the frame 118).

In embodiments employing the sheet of frame sections 443, once the firstand second layers 400 and 404 of pouch material have been sealed aroundthe active material 402 and about the frame 118, a plurality of separateframes 118 may be formed by cutting the framework between the openings444 (e.g., along dashed lines 446). Thus, the separate frames 118including the active material 402 sealed between the cut portions of thefirst and second layers 400 and 404 of pouch material may be providedfor further processing into a plurality of separate battery cells 116.The battery cells 116 may include electrodes, such as the tab electrodes129, which may be configured to extend from the active material 402beyond the edges of the frame 118. As discussed above, the frame 118and/or the tab electrodes 129 may include a molded sealing portion incertain areas, such as the edges 426 of the frame 118, to accommodatethe tab electrodes 129 extending from the active material 402.

FIG. 39 illustrates a battery cell 116 including features configured tofacilitate filling the frame 118 with electrolyte and/or degassing thebattery cell 116 to activate the battery cell 116. To fill the batterycell 116, the first and second layers 400 and 404 of pouch material maybe partially sealed around a perimeter of the active material 402. Forexample, in some embodiments, the first and second layers 400 and 404are sealed to each other with a seal 509 along three sides of thebattery cell 116, wherein the three sides are indicated by referencenumeral 510 in FIG. 39. This seal 509 forms a bag with an open end alonga fourth side 512.

The frame 118 may include a channel 514 (shown in FIG. 39A) tofacilitate filling and degassing. Indeed, the battery cell 116 may beconnected to a filling machine (not shown) via the channel 514 and thefilling machine may generate a vacuum on the battery cell 116. Next, thefilling machine may introduce a measured amount of electrolyte into thebattery cell 116. Indeed, the electrolyte may fill the cell. While theillustrated channel 514 is generally rectangular, the channel 514 maytake any shape or form, including a groove, an opening, a depression, anotch, a beveled edge, etc. Once the desired amount of electrolyte hasbeen inserted into the battery cell 116, the open side (e.g., the fourthside 512) of the battery cell 116 is given a temporary seal 516, and thebattery cell 116 moves to formation (e.g., initial electrical cycling).

After formation, degassing may be required to remove unwanted gas thatmay build up inside the battery cell 116. To remove this unwanted gas,the temporary seal 516 on the fourth side may be cut away, such as alongdashed line 518. This effectively removes the temporary seal 516 andallows degassing via the resulting opening and the channel 514. Once thedesired amount of gas has been removed, the fourth side 512 of the firstand second pouch layers 400 and 404 are completely (e.g., hermetically)sealed around the active material 402 with what may be referred to as apermanent seal 520 that is formed inside the perimeter of the originaltemporary seal.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful in the sealing andmanufacture of battery cells 116. For example, certain embodiments ofthe present approach enable integration of the frame 118 with pouchmaterial. Thus, a structurally supported battery cell component can beprovided more efficiently than separately providing a frame and a pouchcell. Present embodiments also include techniques for efficientlymanufacturing a large number of battery components by utilizing a commonframework during certain process steps and subsequently dividing thecommon framework into separate components. Furthermore, certainembodiments of the present approach may enable improved sealing inbattery cells 116. By specific example, disposing the first and secondlayers 400 and 404 of pouch material about active material 402, andsealing them to or otherwise about the battery cell frame (e.g., theframe 118), as set forth above, may enable the manufacture of batterycells to include a more robust seal about the active material 402,compared to battery cells that are not sealed as described herein. Assuch, the sealing of the battery cell using the first and second layers400 and 404 of pouch material, as presently disclosed, may generallyenable the production of a more robust battery module 22. The technicaleffects and technical problems in the specification are exemplary andare not limiting. It should be noted that the embodiments described inthe specification may have other technical effects and can solve othertechnical problems.

System and Method for Communicative Interconnect of Battery Cells

In addition to the elements discussed above, the battery module 22includes the interconnect assemblies 128 for electrically connecting thebattery cells 116 of the power assembly 84. As discussed above withrespect to FIG. 7, the interconnect assemblies 128 may facilitateelectrical coupling of the battery cells 116 within the power assembly84. FIG. 40 is a schematic cross-sectional representation of the batterymodule 22, which illustrates two interconnect assemblies 128 with anumber of interconnection devices 138 used to facilitate battery cellconnections. The two interconnect assemblies 128 are disposed one oneach side of the power assembly 84.

In order to provide the desired electrical output from the batteryterminals 24, 26, and 30, the battery cells 116 are electricallyconnected in series or parallel via the interconnect assemblies 128. Asdescribed above, the power assembly 84 includes the multiple batterycells 116 arranged in a stacked orientation relative to each other. Inaddition, as discussed above, each battery cell 116 includes a pair oftab electrodes 129 extending from the battery cell 116. At any giventime, one of the tab electrodes 129 acts as the anode, while theopposite facing tab electrode 129 acts as the cathode for the batterycell 116. The battery cells 116 may be connected in series or inparallel to neighboring battery cells 116 as desired. In the illustratedembodiment, the battery cells 116 are all connected in series. Tofacilitate this connection, the interconnection devices 138 may connectthe anode of each battery cell 116 to the cathode of the neighboringbattery cell 116, such that electricity flows through all of the batterycells 116 in series. To that end, the battery cells 116 may be disposedin a stacked orientation such that the direction of the flow ofelectricity through each battery cell 116 switches between alternatingbattery cells 116 within the power assembly 84, as indicated by arrows522. Thus, on each interconnect assembly 128, the interconnectiondevices 138 may be placed between every other pair of neighboringbattery cells 116. The term “neighboring battery cells” is used in thepresent disclosure to mean battery cells 116 that are stacked relativeto each other without any other battery cells 116 disposed between. Afirst battery cell 116 of the power assembly 84 may be electricallycoupled with a second neighboring battery cell 116 via aninterconnection device 138 of the first interconnect assembly 128. Thesecond battery cell 116 may be electrically coupled with a thirdneighboring battery cell 116 via an interconnection device 138 of thesecond interconnect assembly 128, and the third battery cell 116 may beelectrically coupled with a fourth neighboring battery cell 116 via aninterconnection device 138 of the first interconnect assembly 128, andso forth.

Although the illustrated embodiment specifically shows the battery cells116 connected in series via the interconnect assemblies 128, otherembodiments may be possible as well. For example, the battery cells 116may be arranged in the stacked orientation such that anodes of twoneighboring battery cells 116 are coupled via one of the interconnectiondevices, thereby facilitating a parallel connection of the battery cells116. The battery cells 116 and interconnect assemblies 128 may bearranged to allow for any desired combination of parallel and/or seriesconnections between the battery cells 116 of the power assembly 84.Further, it should be noted that the interconnect assemblies 128 andinterconnection devices 138 disclosed herein may be used in applicationsfor connecting any two terminals of an electrical device, such as forconnecting terminals of a fuse with tab electrodes.

In present embodiments, the interconnect assemblies 128 useinterconnection devices 138 configured to receive and facilitateelectrical coupling of two tab electrodes 129 extending from neighboringbattery cells 116. The interconnection devices 138 may be selectivelyremovable from the tab electrodes 129, allowing any one of the batterycells 116 to be disconnected and removed from the power assembly 84 asdesired. Different embodiments of the power module 22 may employdifferent types of interconnection devices 138. For example, in someembodiments described below, the interconnection device 138 may includea clamp configured to be disposed over a coupling structure of theinterconnect assembly 128.

System and Method for Clamping Interconnection of Battery Cells

FIG. 41 is an exploded perspective view of one such embodiment of theinterconnect assembly 128 that can connect neighboring battery cells 116of the battery module 22. As discussed above with respect to FIG. 7, theillustrated interconnect assembly 128 includes the cell interconnectboard 130 (e.g., ladder), which may provide structural support for theinterconnection of the battery cells 116. The cell interconnect board130 also may provide support for connecting the battery cells 116 withthe various sensors 132 disposed on the cell interconnect board 130. Asillustrated, the cell interconnect board 130 includes slots 134 throughwhich the tab electrodes 129 of two neighboring battery cells 116 may bepositioned for connecting the tab electrodes 129. In addition, the cellinterconnect board 130 includes coupling structures 524 disposed acrossthe slots 134 formed in the cell interconnect board 130.

The coupling structures 524 are substantially parallel structuresdisposed as rungs between frame pieces 526 (e.g., opposing edges) of thecell interconnect board 130. Each coupling structure 524 may have asubstantially uniform cross section extending longitudinally between theframe pieces 526 along a longitudinal axis 528. The term “substantiallyparallel” used above refers to longitudinal axes 528 of the couplingstructures 524 being parallel. For example, in the illustratedembodiment, the coupling structures 524 are aligned with respectivelongitudinal axes 528, and these longitudinal axes 528 are substantiallyparallel (e.g., within less than 1, 2, 3, 4, 5, or 6 degrees) of the Xaxis 44 of the battery module 22.

To connect two tab electrodes 129, the tab electrodes 129 may extendthrough the slots 134 and be at least partially conformed to an outersurface of the coupling structure 524 disposed across the slot 134. Eachcoupling structure 524 of the cell interconnect board 130 is positionedand designed to abut or receive the tab electrodes 129 from two batterycells 116 located near the coupling structure 524. In some embodiments,that is, the cell interconnect board 130 may be designed such that thecoupling structures 524, when the battery module 22 is assembled, aredisposed at a position between the tab electrodes 129 extending from twoneighboring battery cells 116, with respect to the Y axis 42.

In addition to the cell interconnect board 130, the interconnectassembly 128 includes a number of interconnection devices 138, which areclamps 530 in the illustrated embodiment. The clamps 530 are configuredto be disposed about the coupling structures 524 to facilitateelectrically coupling the two tab electrodes 129 that are conformed tothe coupling structure 524. More specifically, each clamp 530 may securetwo neighboring tab electrodes 129 between a respective couplingstructure 524 and the clamp 530. One or both of the coupling structure524 and the clamp 530 may be electrically conductive, in order tofacilitate the electrical connection between the two tab electrodes 129.In embodiments where the coupling structure 524 is conductive, the clamp530 is used to secure the tab electrodes 129 in engagement with thecoupling structure 524. In some embodiments, the coupling structure 524and the clamp 530 may be nonconductive, but they may hold the tabelectrodes 129 in direct contact with each other for establishing thedesired electrical connection. The clamps 530 may extend along most orall of the length of the coupling structures 524 to provide a secureconnection. As discussed in detail below, the clamps 530 and thecoupling structures 524 may include specific mating features foraligning and securing the clamps 530 around the respective couplingstructures 524. For example, the clamps 530 may include curved portionsof a spring element that are complementary to substantially roundedouter portions of the coupling structures 524.

In some embodiments, the cell interconnect board 130 may include sensors132 in electrical communication with the coupling structures 524. Insuch embodiments, the coupling structures 524 are conductive, and thecell interconnect board 130 may be part of a PCB that uses electricalsensor measurements to monitor operations of the individual batterycells 116, among other things. Specific embodiments of the sensors 132and methods of connecting sensor electrical contacts with the tabelectrodes 129 are discussed in further detail below.

It should be noted that the interconnect assembly 128 illustrated inFIG. 41 represents one of two interconnect assemblies 128 that may beused together to electrically connect the battery cells 116 in series.That is, one set of the cell interconnect board 130 and clamps 530 maybe disposed at one end of the power assembly 84, and another set of thecell interconnect board 130 and clamps 530 may be disposed at anopposite end of the power assembly 84. As discussed with reference toFIG. 40, the tab electrodes 129 of alternating pairs of the batterycells 116 may be connected via the cell interconnect board 130 andclamps 530 at each end, respectively, until the battery cells 116 areall connected in series via the two interconnect assemblies 128. Inother embodiments, parallel connections may be employed.

Although the illustrated embodiment shows the interconnect assembly 128having the cell interconnect board 130 and a plurality of clamps 530, itshould be noted that other types of interconnection devices 138 may beapplied similarly to tab electrodes 129 conformed to structural rungs ofthe cell interconnect board 130. In other embodiments, that is, the cellinterconnect board 130 may be equipped with different types of couplingstructures 524, and the interconnection devices 138 may take a form thatdiffers from those illustrated in FIG. 41. Examples of such otherembodiments of the interconnect assembly 128 are discussed in detailbelow.

Having now discussed the general arrangement of components within anembodiment of the interconnect assembly 128, detailed descriptions ofpossible interconnection devices 138 will be provided. FIG. 42, forexample, is a perspective view of the clamp 530 discussed above, whichmay facilitate the electrical connection of two tab electrodes 129. Theclamp 530 may be a single-piece spring element. That is, the clamp 530may be formed from a single piece of metal that is flexible enough toapply a desired clamping force to the tab electrodes 129 and thecoupling structure 524. The clamp 530 may provide this clamping forcewithout the application of a force from another component of the batterymodule 22. As described below, the clamp 530 may have a specific shapeto facilitate application, alignment, and removal of the clamp 530relative to the coupling structure 524.

As illustrated, the clamp 530 may be secured about the tab electrodes129 and the coupling structure 524 without the use of additionalfasteners. That is, no separate fastening elements (e.g., screws, pins,bolts, or other connectors) are used to couple and secure the clamp 530against the coupling structure 524. The clamp 530 may be secured aboutthe coupling structure without the use of a fastening element that isseparate from the clamp and the coupling structure. The clamp 530 mayprovide all of the force for maintaining the tab electrodes 129 inposition between the coupling structure 524 and the clamp 530 entirelyfrom the clamping force provided by the spring element. This mayfacilitate relatively easy removal of the clamp 530 from the couplingstructure 524 and the tab electrodes 129, compared to traditionalcouplings that use screws and similar fasteners.

In the illustrated embodiment, the clamp 530 has a uniform cross sectionthat extends along an axis 532 of the clamp 530. The clamp 530 mayextend in the direction of the axis 532 for a length that isapproximately equal to (e.g., within 5 mm of) or slightly less than(e.g., within 20 mm of) a length of the coupling structure 524 aboutwhich the clamp 530 is positioned. In some embodiments, the clamp 530extends beyond the coupling structure 524 to ensure full engagement. Theclamp 530 may extend a distance along the axis 532 that is larger than acorresponding dimension of the tab electrodes 129 extending from thebattery cells 116. This may help to ensure a proper electrical couplingof the tab electrodes 129 along the entire edge of each of the tabelectrodes 129.

The shape of the cross section of the clamp 530 may include, among otherthings, a pair of curved portions 534, a detent 536 disposed between thecurved portions 534, and wings 538 extending from ends 540 of the curvedportions 534. This type of clamp 530 may be used with rounded couplingstructures 524, such as a substantially cylindrical bar. Indeed, thecurved portions 534 may function as components of a spring element toengage a substantially rounded outer portion of the coupling structure524. That is, the curved portions 534 of the clamp 530 may partiallytrace a substantially rounded perimeter or partial perimeter of thecoupling structure 524 with a geometric center. In the illustratedembodiment, for example, the curved portions 534 partially trace acircle, although in other embodiments, the curved portions 534 may tracean oval or other rounded geometric shape. The detent 536 may be disposedbetween the curved portions 534 at a position midway between the ends540 of the clamp 530. The detent 536 extends toward a center of thecircle (or other rounded shape) traced by the curved portions 534. Thedetent may be captured in an indentation of the coupling structure 524,thereby securing the clamp 530 about the coupling structure 524 in arelatively fixed orientation. The two wings 538 may extend from thecurved portions 534 such that they are angled away from the center ofthe circle (or other rounded shape) traced by the curved portions 534.

The wings 538 may facilitate alignment with or removal of the clamp 530from the coupling structure 524. Specifically, the wings 538 may bepulled apart, manually or via a tool, to remove the curved portions 534of the clamp 530 from the coupling structure 524. In the illustratedembodiment, the wings 538 include apertures 542 that may receiveextensions from a tool that can be actuated to flex the clamp 530 openfor coupling or decoupling with the coupling structure 524.Specifically, the extensions from the tool may be inserted into theapertures 542 and a levering action initiated by squeezing plier-likehandles of the tool together may cause the clamp 530 to flex open. Whenit is desirable to remove a battery cell 116 with a tab electrode 129secured between the clamp 530 and the coupling structure 524, anoperator may pull the wings 538 apart, and remove the clamp 530 from thecoupling structure 524 and the tab electrode 129.

FIG. 43 is a schematic cross-sectional view of the interconnect assembly128 having the coupling structure 524 and the clamp 530. In theillustrated embodiment, the interconnect assembly 128 is used toelectrically couple a first tab electrode 129 extending from a firstbattery cell 116 with a second tab electrode 129 extending from a secondbattery cell 116. As discussed above, the battery cells 116 are disposedin a stacked orientation relative to one another. In the illustratedembodiment, the tab electrodes 129 are secured between the couplingstructure 524, which may be electrically conductive, and the clamp 530.

To secure the tab electrodes 129 in the illustrated position, the clamp530 is disposed about the coupling structure 524 and the first andsecond tab electrodes 129. More specifically, the clamp 530 may bepositioned such that the curved portions 534 of the clamp 530 abut thetab electrodes 129 that are partially conformed around the couplingstructure 524. From this position, the curved portions 534 of the clamp530 may push against the rounded outer edge of the coupling structure524, exerting a clamping force that maintains the tab electrodes 129securely between the coupling structure 524 and the clamp 530.

It should be noted that the illustrated embodiments include curvedclamps 530 (e.g., with the curved portions 534) configured to bereceived over rounded coupling structures 524. Using such rounded shapesfor the electrical coupling of the tab electrodes 129 may facilitate arelatively enhanced connection, compared to maintaining tab electrodesagainst relatively flat structures. For example, a larger surface areaof the tab electrodes 129 may be held between the rounded clamp 530 andcoupling structure 524 than between a flat clamp/coupling structure thattakes up a comparable amount of space in the battery module 22. This mayfacilitate a more secure connection between the tab electrodes 129,especially when the electrical connection requires direct contact of thetab electrodes 129 with one or both of the coupling structure 524 andthe clamp 530. In addition, the rounded clamp 530 may apply the clampingforce to the rounded coupling structure 524 such that the spring forcein the clamp 530 is applied to the coupling structure 524 and the tabelectrodes 129 from several different directions. Instead of twoopposing friction force vectors directed to the coupling structure 524and the tab electrodes 129, the disclosed clamp 530 provides radialclamping force vectors directed toward the center of the couplingstructure 524. This may facilitate a relatively secure connection of theclamp 530 around the coupling structure 524, preventing the clamp 530from sliding off or being unintentionally pulled out of connection withthe coupling structure 524.

In some embodiments, the clamp 530 and the coupling structure 524 may besized appropriately for holding the tab electrodes 129 via the clampingforce. As noted above, the curved portions 534 of the clamp 530 maytrace a circle. In the illustrated embodiment, the coupling structureincludes a substantially cylindrical bar. In some embodiments, adiameter of the circled traced by the curved portions 534 of the clamp530 may be approximately the same size, or slightly smaller than, anouter diameter of a rounded portion 544 of the cylindrical bar. Sincethe rounded portion 544 of the coupling structure 524 receives thecurved portions 534 of the clamp 530, the clamp 530 may be elasticallydeformed when placed over the coupling structure 524 and the tabelectrodes 129. As the clamp 530 exerts a spring force to bring theclamp 530 back into its equilibrium position, the clamp 530 transfersthe force (as a clamping force) to the tab electrodes 129 and thecoupling structure 524 via the curved portions 534.

As noted above, the coupling structure 524 and the clamp 530 may includecomplementary mating features for aligning and securing the clamp 530about the coupling structure 524. Such mating features may include, forexample, an indentation and detent. The illustrated coupling structure524 is a substantially cylindrical bar, meaning that the bar iscylindrical except for an indentation 546 (e.g., a groove) formed alongthe outer diameter of the bar. This indentation 546 may extend along thelength of the coupling structure 524. In other embodiments, theindentation 546 may be a recess, concavity, or multiple such features.The indentation 546 may be complementary with respect to the detent 536of the clamp 530. That is, the indentation 546 may be sized to receivethe detent 536 of the clamp 530 when the clamp 530 is disposed aroundthe coupling structure 524 and the tab electrodes 129. By receiving andholding the detent 536 in the indentation 546, the coupling structure524 may secure the clamp 530 in position about the coupling structure524, so that the clamp 530 does not rotate with respect to or come offthe coupling structure 524 on its own. In addition, the indentation 546and the detent 536 may facilitate an appropriate rotational alignment ofthe clamp 530 relative to the coupling structure 524. Specifically, theplacement of the indentation 546 and the complementary detent 536 maymaintain the clamp 530 in position such that the curved portions 534 ofthe clamp 530, which transfer the clamping force, are situated directlyover the tab electrodes 129 that are partially conformed to the couplingstructure 524. Other arrangements of indentations 546 and complementarydetents 536 may be employed in other embodiments of the interconnectassembly 128. For example, the indentation 546 is replaced with anextension (e.g., ridge or prong) in some embodiments, while the detent536 is correspondingly replaced with a receptacle for the extension.

As noted above, the wings 538 of the clamp 530 may be used to remove theclamp 530 from the coupling structure 524. Specifically, an operator maymanually, or with a tool, pull the wings 538 in the directions shown byarrows 548 in the illustrated embodiment. When pulled, the wings 538 mayact as levers to force at least part of the curved portions 534 of theclamp 530 out of contact with the coupling structure 524 and the tabelectrodes 129. Once the curved portions 534 are no longer securedaround the coupling structure 524, the clamp 530 may be removed from thecoupling structure 524 and the tab electrodes 129. The clamp 530 may beremoved from the coupling structure 524 in a direction of the positive Zaxis 40, as shown by an arrow 550.

The clamp 530 may be inserted onto the coupling structure 524 in anopposite direction (e.g., negative Z axis 40), as illustrated by arrow552 in FIG. 44. However, prior to insertion of the clamp 530, the firstand second tab electrodes 129 may be pre-shaped to conform at leastpartially to the coupling structure 524. More specifically, the tabelectrodes 129 may be brought toward the coupling structure 524 and bentaround the corresponding rounded portions 544 of the coupling structure524, as shown by arrows 553. The coupling structure 524 receives the tabelectrodes 129 in this conforming orientation with respect to thecoupling structure 524 before the clamp 530 is disposed thereon. Whenthe clamp 530 is added, the wings 538 are received over the couplingstructure 524 and the pre-shaped tab electrodes 129, then the curvedportions 534 are received over the coupling structure 524, and thedetent 536 is positioned within the complementary indentation 546 of thecoupling structure 524.

In the illustrated embodiment the tab electrodes 129 are pre-shaped suchthat they already conform to the coupling structure 524. That is, thepre-shaped tab electrodes 129 are in direct contact with the couplingstructure 524 prior to the application of the clamp 530. However, inother embodiments, the tab electrodes 129 may be pre-shaped such thatthey are not directly in contact with the coupling structure 524 untilthe clamp 530 is disposed over the tab electrodes 129 and the couplingstructure 524. In such instances, the clamp 530 pushes the tabelectrodes 129 against the coupling structure 524 to establish theelectrical connection.

Although in the illustrated embodiment, the tab electrodes 129 arewrapped only partially around the coupling structure 524, in otherembodiments, the tab electrodes 129 may extend far enough from thebattery cells 116 to wrap around the coupling structure 524 until thetab electrodes 129 are touching each other. In such instances, thecoupling structure 524 and/or the clamp 530 may not be conductive at allfor establishing an electrical connection between the tab electrodes129. Instead, the tab electrodes 129 themselves may be pre-shaped aroundthe coupling structure 524 until they are overlapping with respect toeach other. Then, the clamp 530 may be positioned on the couplingstructure 524 to secure the tab electrodes 129 in direct contact witheach other for providing the electrical connection. In still otherembodiments, the clamp 530 may be conductive, so that the electricalconnection is established via the clamp 530.

Other variations of the coupling structure 524 may be possible as well.For example, as illustrated in FIG. 45, the coupling structure 524 mayinclude a substantially cylindrical bar 554 that is hollow. This mayreduce an overall weight of the battery module 22, as compared to asolid cylindrical bar. In other embodiments, the coupling structure 524may include a clamp structure designed to receive the clamp 530. Anexample of one such clamp structure 555 is shown in FIG. 46. In theillustrated embodiment, the clamp structure 555 is complementary withrespect to the clamp 530, meaning that the clamp structure 555 includesfeatures designed to interact with and receive features of the clamp530. The clamp structure 555 may be a single piece spring element,similar to the clamp 530, and may include similar features to the clamp530. Specifically, the clamp structure 555 may include one or more ofcurved portions 556, wings 557 extending from the curved portions 556,and a detent 558 extending between the curved portions 556. The detent558 may function as an indentation for receiving and holding the detent536 of the clamp 530 against the clamp structure 555. One or both of theclamp structure 555 and the clamp 530 may be electrically conductive toprovide an electrical connection between the two tab electrodes 129secured between the clamp structure 555 and the clamp 530. Otherembodiments of the interconnect assembly 128 may utilize different typesof coupling structures 524 than those shown in the present disclosure.

One or more of the disclosed embodiments, alone or in combination, mayprovide one or more technical effects useful in the assembly andmaintenance of battery modules with a number of battery cells arrangedin a stacked orientation relative to each other. For example, certainembodiments of the present approach may enable improved interconnectionsbetween tab electrodes extending from the different battery cells. Byspecific example, conforming the tab electrodes around a couplingstructure and securing the tab electrodes in electrical communicationwith each other via a clamp, as set forth above, may enable easierconnections and disconnections of the battery cells, compared to batteryinterconnect assemblies that rely on relatively permanent connectionmethods, such as laser welding. The presently disclosed interconnectassembly provides a simple mechanical clamp that facilitates electricalcoupling of the tab electrodes. Such clamps may be relatively easy tomanufacture, as they can be formed from a single spring element. Theclamp may includes features (e.g., wings) that facilitate removal of theclamp from the tab electrodes and the coupling structure, making thedisclosed interconnect assembly more versatile than laser welding andother existing techniques for the disconnection, removal, or replacementof individual battery cells in the battery module. As such, theinterconnection of battery cells via a clamp and coupling structure maygenerally enable a battery module with a more simple assembly and withindividually replaceable battery cells. The technical effects andtechnical problems in the specification are exemplary and are notlimiting. It should be noted that the embodiments described in thespecification may have other technical effects and can solve othertechnical problems.

System and Method for Crimping Interconnection of Battery Cells

As noted above, other types of interconnection devices 138 may beemployed in the interconnect assembly 128. For example, FIG. 47illustrates an embodiment of the interconnect assembly 128 that uses acrimping element 560 to hold the tab electrodes 129 in direct contact,and thus in electrical communication, with each other. Specifically, thecrimping element 560 is disposed over the tab electrodes 129, and thecrimping element 560 is configured to apply a compressive force to thetab electrodes 129, as illustrated by arrows 562. The crimping element560 may include a spring element that naturally biases aspects of thecrimping element 560 in the direction of arrows 562 or the crimpingelement 560 may include a pliable material that essentially maintainsits shape after being pressed together in the direction of arrows 562.In some embodiments, the crimping element 560 is electrically conductiveto facilitate electrically coupling the tab electrodes 129 extendingfrom the two battery cells 116. However, in other embodiments, thecrimping element 560 may be nonconductive and may simply compress thetwo tab electrodes 129 against one another to maintain an electricalconnection via direct contact. It should be noted that the tabelectrodes 129 are representative of one embodiment and presentembodiments may also be utilized with different types of electrodes.

The crimping element 560 may take on a variety of forms in differentembodiments, each utilizing specific features to apply the compressiveforce to the tab electrodes 129. For example, in one embodiment, thecrimping element 560 may include a single-piece spring element. Asdescribed in detail below, the single-piece spring element may be shapedto apply a desired compressive force for holding the tab electrodes 129together. The shape of the spring element may also be designed tofacilitate attachment and removal of the crimping element 560 from thetab electrodes 129 (e.g., via a tool). In another embodiment discussedbelow, the crimping element 560 may include a clip assembly with abiasing feature that facilitates opening and closing of the clip. Thisallows the clip to be selectively attached to or removed from the tabelectrodes 129. In yet another embodiment, the crimping element 560incorporates soft or pliable material (e.g., soft metal) and/orcomponents with adhesive disposed thereon that can be pressed intoengagement about the tab electrodes 129 such that the crimping element560 maintains a compressed shape and thus a compressive coupling withthe tab electrodes 129.

In the illustrated embodiment of FIG. 48, the crimping element 560 mayinclude high voltage tape 564, which may include pliable metal. The highvoltage tape 564 may be any adhesive tape that includes an adhesivelayer 565 and, when disposed over the tab electrodes 129, permits theflow of electricity between the tab electrodes 129. The high voltagetape 564 may include, for example, electrical tape (e.g., insulatingtape) or conductive tape. The adhesive (e.g., adhesive layer 565) of thehigh voltage tape 564 may maintain a compressive force on the tabelectrodes 129, the compressive force being initially established duringattachment of the high voltage tape 564. That is, the compressive forceis first applied by an operator (or tool) that applies pressure to twosides 566 of the high voltage tape 564 disposed around the tabelectrodes 129, and this pressure is maintained as the high voltage tape564 sticks to itself via the adhesive 565. Although not illustrated, thehigh voltage tape 564 may extend past the tab electrodes 129 along the Xaxis 44 so that the two sides 566 can be secured together. The highvoltage tape 564 may be removable. A user may pull the sides 566 of thehigh voltage tape 564 apart to disconnect the tab electrodes 129. Insome embodiments, the high voltage tape 564 may be reusable, so that itcan be attached and removed several times before being discarded. Thus,the high voltage tape 564 may be a relatively inexpensive and flexibleelement for removably crimping the tab electrodes 129 into electricalcontact.

As noted above, the interconnect assembly 128 includes the crimpingelement 560, which may be a spring element, a clip, tape, or some othercomponent for compressing the tab electrodes 129 together. In theillustrated embodiment of FIG. 47 the interconnect assembly 128 alsoincludes the coupling structure 524, which is configured to receive thetab electrodes 129 in a partially conforming orientation with respect tothe coupling structure 524. That is, respective portions of the tabelectrodes 129 extend over a portion of the coupling structure 524 andflexibly engage the contacted portion of the coupling structure 524 suchthat the tab electrodes 129 assume geometries in partial conformancewith the coupling structure 524. This type of conformity of the tabelectrodes 129 with the coupling structure 524 occurs in accordance withvarious embodiments that employ the coupling structure 524. The two tabelectrodes 129 are described as being partially conformed about thecoupling structure 524 because they include sections that conform orsubstantially conform to certain surfaces of the coupling structure 524.That is, portions of the tab electrodes 129 that abut the couplingstructure 524 flex and bend about the coupling structure 524 such thatthe tab electrodes 129 trace certain contours of the coupling structure524. This conformed orientation of the tab electrodes 129 to thecoupling structure 524 is illustrated in each of FIGS. 47, 49, 50, and51. It should be noted that the tab electrodes 129 may be pre-shaped bya crimping mechanism prior to positioning the tab electrodes 129adjacent the coupling structure 524 to encourage the conformedorientation. Once the tab electrodes 129 are arranged with respect tothe coupling structure 524 (whether pre-shaped or partially conformed),the crimping element 560 may be disposed against the tab electrodes 129to secure the tab electrodes 129 in electrical communication with eachother.

The crimping element 560 may secure the tab electrodes 129 in theconforming orientation around the coupling structure 524. The crimpingelement 560 and the coupling structure 524 are separate components ofthe illustrated interconnect assembly 128. In some embodiments, thecoupling structure 524 may be electrically conductive to facilitate theelectrical connection of the tab electrodes 129 that are held inposition against the coupling structure 524 via the crimping element560. The coupling structure 524 may provide a substantial conductivesurface for electrical interaction with the tab electrodes 129 and/orstructural support for the tab electrodes 129 and the correspondinginterconnection devices 138. However, it should be noted that, in someembodiments, the coupling structure 524 is not utilized and the crimpingelement 560 or other interconnection devices 138 function in a mannersimilar to that illustrated in FIG. 40.

FIG. 49 is a perspective sectional view of the interconnect assembly 128that uses crimping elements 560 to secure pairs of the tab electrodes129 around corresponding coupling structures 524. In the illustratedembodiment, the coupling structures 524 form part of the cellinterconnect board 130 of the interconnect assembly 128, which wasdiscussed in detail above with respect to FIG. 41. The cell interconnectboard 130 may provide structural support for the interconnection of thetab electrodes 129 via the crimping elements 560. As noted above, thecell interconnect board 130 may also provide support for theinterconnection of the battery cells 116 with the various sensors 132.Again, the cell interconnect board 130 includes the slots 134 throughwhich the tab electrodes 129 of neighboring battery cells 116 may bepositioned for connecting the tab electrodes 129. The couplingstructures 524 are disposed across the slots 134 formed in the cellinterconnect board 130. As discussed above with respect to FIG. 41, thecoupling structures 524 may be substantially parallel structuresdisposed as rungs between the frame pieces 526 (e.g., opposing edges) ofthe cell interconnect board 130. Only one of the frame pieces 526 isshown in the illustrated embodiment.

To connect two tab electrodes 129, the tab electrodes 129 may extendthrough the slots 134 and be at least partially conformed to an outersurface of the coupling structure 524 disposed across the slot 134. Eachcoupling structure 524 of the cell interconnect board 130 is positionedand designed to abut or receive the tab electrodes 129 from two batterycells 116 located near the coupling structure 524. In some embodiments,that is, the cell interconnect board 130 may be designed such that thecoupling structures 524, when the battery module 22 is assembled, aredisposed proximate the respective pair of tab electrodes 129 that are tobe received over the coupling structures 524. That is, the couplingstructures 524 are disposed at a position between the tab electrodes 129extending from two neighboring battery cells 116, with respect to the Yaxis 42.

In some embodiments, the cell interconnect board 130 may include thesensors 132 (not shown) in electrical communication with the couplingstructures 524. In such embodiments, the coupling structures 524 may beconductive, and the cell interconnect board 130 may be part of a PCBthat uses electrical sensor measurements to monitor operations of theindividual battery cells 116, among other things. Specific embodimentsof the sensors 132 and methods of connecting sensor electrical contactswith the tab electrodes 129 are discussed in further detail below. Inone embodiment, for example, the crimping element 560 may be disposedover the tab electrodes 129 and a tab electrical contact extending fromthe PCB and in communication with one or more of the sensors 132. Thecrimping element 560 may electrically couple the tab electrodes 129 fromneighboring battery cells 116 with the tab electrical contact tofacilitate collecting sensor measurements.

The crimping elements 560 may be attached to the pairs of tab electrodes129 disposed around the respective coupling structures 524, holding thetab electrodes 129 in the partially conformed position around thecoupling structures 524. The crimping elements 560 may extend along mostor all of the length of the coupling structures 524 to provide a secureconnection. In some embodiments, the crimping elements 560 may engagethe coupling structures 524 and the tab electrodes 129. However, inother embodiments, the crimping elements 560 may facilitate coupling ofthe tab electrodes 129 in the partially conformed position around thecoupling structures 524 without the crimping elements 560 being placedin contact with the coupling structures 524. In the illustratedembodiment, each crimping element 560 has a uniform cross section thatextends along a lengthwise axis 568 of the crimping element 560. Thecrimping element 560 may extend in the direction of the axis 568 for alength that is approximately equal to (e.g., within 5 mm) or slightlyless than (e.g., within 20 mm) a length of the coupling structure 524about which the crimping element 560 is positioned. In some embodiments,the crimping element 560 extends beyond the coupling structure 524 toensure full engagement. The crimping element 560 may extend a distancealong the axis 568 that is larger than a corresponding dimension of thetab electrodes 129 extending from the battery cells 116. This may helpto ensure a proper electrical coupling of the tab electrodes 129 alongthe entire edge of each of the tab electrodes 129.

It should be noted that the crimping element 560 may be secured aboutthe tab electrodes 129 without the use of additional fasteners. That is,no separate fastening elements (e.g., screws, pins, bolts, or otherconnectors) are used to couple and secure the crimping element 560 aboutthe tab electrodes 129. The crimping element 560 may secure the tabelectrodes 129 together without the use of a fastening element that isseparate from the crimping element 560. The crimping element 560 mayprovide all of the force for maintaining the tab electrodes 129 inposition around the coupling structure 524 entirely from the compressiveforce provided by the crimping element 560. This may facilitaterelatively easy removal of the crimping element 560 from the tabelectrodes 129, compared to traditional couplings that use screws andsimilar fasteners.

In the illustrated embodiment, the crimping element 560 is a shapedspring element 570 with a substantially uniform cross section extendingalong the axis 568. FIG. 50 is a schematic cross-sectional view of thespring element 570, illustrating the specific shape of the springelement 570 that facilitates the compressive force for electricallycoupling the tab electrodes 129. FIG. 50 also shows a detailed view ofthe shape of the coupling structure 524 around which the tab electrodes129 are secured via the spring element 570.

The illustrated coupling structure 524 has a U-shaped cross section withtwo substantially parallel arms 572 extending from opposite ends of abase portion 574 of the coupling structure 524. In the illustratedembodiment, the arms 572 are substantially parallel to (e.g., within 1,2, 3, 4, 5, or 6 degrees of) the Z axis 40. The base portion 574 issubstantially parallel to the Y axis 42, and the arms 572 extend fromthe base portion 574 toward the battery cells 116 of the battery module22. As noted above, the coupling structure 524 is configured to receivethe pair of tab electrodes 129 in a conforming orientation. In theillustrated embodiment, each tab electrode 129 is conformed around oneof the arms 572, and the crimping element 560 (e.g., spring element 570)secures the tab electrodes 129 along the base portion 574 of thecoupling structure 524. It should be noted that although the illustratedcrimping element 560 is a spring element 570, other types of crimpingelements 560 may be used to secure the tab electrodes 129 against thebase portion 574 of the U-shaped coupling structure 524.

As mentioned above, the illustrated spring element 570 is shaped toapply or provide the compressive force for securing the tab electrodes129 in contact with each other. The spring element 570 may be asingle-piece spring element, meaning that it is constructed (e.g., bent,forged, cast, or otherwise manufactured) from a single piece of flexiblematerial. The shape of the cross section of the spring element 570 mayinclude, among other things, a pair of arms 576 angled toward eachother, a connecting portion 578 located between the arms 576, and a pairof curved portions 580 located one at each end of the respective arms576. The arms 576 form opposing ends of the spring element 570, and thearms 576 are biased toward each other to provide the compressive force.Specifically, the connecting portion 578 biases the arms 576 toward eachother to provide the compressive force to the tab electrodes 129disposed between the arms 576. The curved portions 580 function as endseparation features of the spring element 570. The curved portions 580extend away from a point of application of the compressive force (e.g.,where the arms 576 contact the tab electrodes 129). The curved portions580 may be engaged and separated from each other to facilitate removalof the spring element 570 from the tab electrodes 129 via separation ofthe arms 576.

The spring element 570 may be initially constructed such that the arms576 are in contact with each other before the spring element 570 isdisposed over the tab electrodes 129. The arms 576 may be separated,either manually or with a tool, and the spring element 570 may bepositioned over the tab electrodes 129 such that the tab electrodes 129are disposed between the opened arms 576. The arms 576 may be released,and a spring force stored in the connecting portion 578 may urge thearms 576 back toward each other, thus capturing the tab electrodes 129between the arms 576. It may be desirable to remove one or more of thebattery cells 116 (for replacement or servicing) from the battery module22 by disconnecting the tab electrodes 129 from each other. Todisconnect the tab electrodes 129, an operator may lift, pull, orotherwise engage (manually or with a tool) the curved portions 580, inorder to separate the arms 576 and remove the spring element 570 fromthe tab electrodes 129.

FIG. 51 illustrates a removal of the spring element 570 from the tabelectrodes 129 using a tool. In the illustrated embodiment, the curvedportions 580 of the spring element 570 may receive one or more toolsthat can be actuated to flex the spring element 570 open for coupling ordecoupling with the tab electrodes 129. Specifically, tool features 582may be inserted into the curved portions 580 and a levering actioninitiated by squeezing the tool features 582 together in a plier-likemanner may cause the spring element 570 to flex open, as shown by arrows584. The tool features 582 may engage the curved portions 580 located atthe ends of the spring element 570 and urge the curved portions 580apart to remove the compressive force from the tab electrodes 129. Thespring element 570 and tab electrodes 129 may then be moved out ofcontact with each other so that the tab electrodes 129 are no longerconnected. An operator may then remove one or both of the battery cells116 from the battery module 22.

Other types of crimping elements 560 may be used for the interconnectiondevices 138 of the interconnect assembly 128. For example, FIG. 52illustrates an embodiment of the crimping element 560 that includes aclip assembly 586 designed to secure the tab electrodes 129 inelectrical contact with each other via a compressive force. The clipassembly 586 includes two rigid arms 588 coupled via a biasing feature,such as a spring 590. As illustrated, the two arms 588 are biased towardeach other at a first end 592, and away from each other at a second end594 opposite the first end 592. An operator may squeeze the arms 588 ina plier-like manner at the second end 594. This may compress the spring590 or other biasing feature and separate the arms 588 at the first end592, thereby releasing the tab electrodes 129 from contact with eachother and the clip assembly 586. The arms 588 are also attached to afulcrum 595 disposed between the spring 590 and the clamping end (i.e.,first end 592) of the arms 588. In this position, the fulcrum 595functions as a pivot point for the clip assembly 586. Specifically, thefulcrum 595 may transfer the separating force that the spring 590 exertson the arms 588 at the second end 594 into a compressive force on thearms 588 at the first end 592. Likewise, the fulcrum 595 may transfer aforce applied by the operator compressing the spring 590 at the secondend 594 into a separating force at the first end 592.

Although not shown, the illustrated interconnect assembly 128 mayinclude the coupling structure 524. That is, the clip assembly 586 maybe used to secure the tab electrodes 129 against the coupling structure524 to electrically connect the tab electrodes 129. In some embodiments,however, the crimping element 560 (e.g., high voltage tape 564, springelement 570, clip assembly 586, or some other crimping element) may bedisposed over the tab electrodes 129 without the tab electrodes 129being conformed to a structural component of the battery module 22. Thismay be possible depending on the length of the tab electrodes 129extending from the battery cells 116 and the relative weight of thecrimping element 560 to the tab electrodes 129. It may be desirable forthe interconnect assembly 128 to include the tab electrodes 129 disposedin a conformed orientation with respect to the coupling structure 524when the tab electrodes 129 are relatively long and/or when the crimpingelement 560 is relatively heavy in comparison with the tab electrodes129. As noted above, the coupling structure 524 may provide structuralsupport, surface area for electrical connection, and so forth. Othertypes, arrangements, and combinations of coupling structures 524 andcrimping elements 560 may be used in other embodiments to facilitatebattery cell interconnections in the battery module 22.

One or more of the disclosed embodiments, alone or in combination, mayprovide one or more technical effects useful in the assembly andmaintenance of battery modules with a number of battery cells arrangedin a stacked orientation relative to each other. For example, certainembodiments of the present approach may enable improved interconnectionsbetween tab electrodes extending from the different battery cells. Byspecific example, securing the tab electrodes in electricalcommunication with each other via a crimping element, as set forthabove, may enable easier connections and disconnections of the batterycells, compared to battery interconnect assemblies that rely onrelatively permanent connection methods, such as laser welding. Thepresently disclosed interconnect assembly provides a simple mechanicalcrimping element that facilitates electrical coupling of the tabelectrodes. Such crimping elements may be relatively inexpensive andeasy to manufacture. The crimping element may include high voltage tape,a clip assembly, or a single-piece spring element. The crimping elementmay utilize a spring or other biasing feature to provide a compressiveforce to hold the tab electrodes in electrical communication with eachother. Other embodiments may employ an adhesive and/or pliable material(e.g., soft metal) that conforms when compressed and generally maintainsthe compressed shape. In addition, presently disclosed interconnectassemblies may also include a coupling structure to provide structuralsupport for interconnecting the tab electrodes and/or providing sensorconnections from each pair of battery cells to a PCB. Further, thecrimping element may include arms that are separable, or other featuresthat aid in removal of the crimping mechanism from the tab electrodes.This makes the disclosed interconnect assembly more versatile than laserwelding and other existing techniques for the disconnection, removal, orreplacement of individual battery cells in the battery module. As such,the interconnection of battery cells via a crimping element maygenerally enable a battery module with a more simple assembly and withindividually replaceable battery cells. The technical effects andtechnical problems in the specification are exemplary and are notlimiting. It should be noted that the embodiments described in thespecification may have other technical effects and can solve othertechnical problems.

System and Method for Roller Interconnection of Battery Cells

Again, other types of interconnection devices 138 may be used in theinterconnect assembly 128. For example, FIG. 53 illustrates anembodiment of the interconnect assembly 128 that uses a roller 596disposed in a corresponding roller housing structure 598 to facilitateelectrically coupling the tab electrodes 129. Specifically, two tabelectrodes 129 are at least partially conformed about each rollerhousing structure 598 such that the tab electrodes 129 are positioned inan opening 600 defined by the roller housing structure 598. The two tabelectrodes 129 are described as being partially conformed about theroller housing structure 598 because they include sections that conformor substantially conform to certain surfaces of the roller housingstructure 598. That is, portions of the tab electrodes 129 that abut theroller housing structure 598 flex and bend about the roller housingstructure 598 such that the tab electrodes 129 trace certain contours ofthe roller housing structure 598. This conformed orientation of the tabelectrodes 129 to the roller housing structure 598 is illustrated ineach of FIGS. 53, 54, 55, 56, and 57. It should be noted that the tabelectrodes 129 may be pre-shaped by a crimping mechanism prior topositioning the tab electrodes 129 adjacent the roller housing structure598 to encourage the conformed orientation. Once the tab electrodes 129are arranged with respect to the roller housing structure 598 (whetherpre-shaped or partially conformed), the roller 596 is disposed in theopening 600 to secure the tab electrodes 129 in electrical communicationwith each other. This insertion of the roller 596 may further conformthe tab electrodes 129 to the contours of roller housing structure 598and the roller 596. That is, the roller 596 may be positioned in theopening 600 to frictionally secure and press the tab electrodes 129between the roller 596 and the roller housing structure 598.

In some embodiments, one or both of the roller housing structure 598 andthe roller 596 may be electrically conductive, in order to facilitatethe electrical connection between the two tab electrodes 129. Inembodiments where the roller housing structure 598 is conductive, theroller 596 is used to secure the tab electrodes 129 in engagement withthe roller housing structure 598. In some embodiments, the rollerhousing structure 598 and the roller 596 may be nonconductive, but theymay hold the tab electrodes 129 in direct contact with each other forestablishing the desired electrical connection. In such embodiments, thetab electrodes 129 overlap with one another within the roller housingstructure 598, in contrast to the positioning of the tab electrodes 129in the embodiment illustrated by FIG. 53.

In the illustrated embodiment, the roller housing structures 598 formpart of the cell interconnect board 130 of the interconnect assembly128, which was discussed in detail above with respect to FIG. 41. Thecell interconnect board 130 may provide structural support for theinterconnection of the tab electrodes 129 via the rollers 596. As notedabove, the cell interconnect board 130 may also provide support for theinterconnection of the battery cells 116 with the various sensors 132.Again, the cell interconnect board 130 includes the slots 134 throughwhich the tab electrodes 129 of neighboring battery cells 116 may bepositioned for connecting the tab electrodes 129. The roller housingstructures 598 are disposed across the slots 134 formed in the cellinterconnect board 130. Similar to the coupling structures 524 of FIG.41, the roller housing structures 598 may be substantially parallelstructures disposed as rungs between the frame pieces 526 (e.g.,opposing edges) of the cell interconnect board 130. Only one of theframe pieces 526 is shown in the illustrated embodiment.

To connect two tab electrodes 129, the tab electrodes 129 may extendthrough the slots 134 and be at least partially conformed to surfaces ofthe roller housing structure 598 disposed across the slot 134. Eachroller housing structure 598 of the cell interconnect board 130 ispositioned and designed to receive the tab electrodes 129 from twobattery cells 116 located near the roller housing structure 598. In someembodiments, that is, the cell interconnect board 130 may be designedsuch that the roller housing structures 598, when the battery module 22is assembled, are disposed proximate the respective pair of tabelectrodes 129 that are to be received over respective surfaces of theroller housing structures 598. That is, the roller housing structures598 are disposed at a position between the tab electrodes 129 extendingfrom two neighboring battery cells 116, with respect to the Y axis 42.It should be noted that, while the illustrated interconnect assembly 128is used to connect battery cells 116 that are disposed in a horizontallystacked orientation relative to each other, the disclosed techniques mayalso be used to electrically couple battery cells 116 disposed in avertically stacked orientation relative to each other. In suchinstances, for example, the roller housing structures 598 may bedisposed at a position between the tab electrodes 129 extending from twoneighboring battery cells 116, with respect to the X axis 44.

In some embodiments, the cell interconnect board 130 may include thesensors 132 (not shown) in electrical communication with the rollerhousing structures 598. In such embodiments, the roller housingstructures 598 may be conductive, and the cell interconnect board 130may be part of a PCB that uses electrical sensor measurements to monitoroperations of the individual battery cells 116, among other things.Specific embodiments of the sensors 132 and methods of connecting sensorelectrical contacts with the tab electrodes 129 are discussed in furtherdetail below.

The rollers 596 may be disposed in the opening 600 defined by the rollerhousing structures 598, holding the tab electrodes 129 in the partiallyconformed position around the roller housing structures 598. The rollers596 may extend along most or all of the length of the roller housingstructures 598 to provide a secure connection. In some embodiments, therollers 596 may extend beyond certain aspects of the respective rollerhousing structures 598. In operation, the rollers 596 may engage theroller housing structures 598 and the tab electrodes 129. In theillustrated embodiment, each roller 596 has a uniform cross section thatextends along a lengthwise axis 602 of the roller 596. Morespecifically, the roller 596 may be a substantially cylindrical bar. Theroller 596 may extend in the direction of the axis 602 for a length thatis approximately equal to (e.g., within 5 mm) or slightly less than(e.g., within 20 mm) a length of the roller housing structure 598 intowhich the roller 596 is positioned. The roller 596 may extend a distancealong the axis 602 that is larger than a corresponding dimension of thetab electrodes 129 extending from the battery cells 116. This may helpto ensure a proper electrical coupling of the tab electrodes 129 alongthe entire edge of each of the tab electrodes 129.

The roller 596 may be configured to be removed manually from the opening600 in the roller housing structure 598. Specifically, the length of theroller 596 extending along the axis 602 may allow for such manualremoval. That is, in some embodiments, the roller 596 may extend adistance that is less than the length of the roller housing structure598. This may provide space between the roller 596 and one or both ofthe frame pieces 526, so that the roller 596 is not positioned flushagainst both of the frame pieces 526 when disposed in the opening 600.Thus, one or both ends of the roller 596 may be accessible to anoperator, so that the operator may grasp the exposed ends of the roller596 and manually remove the roller 596 from the roller housing structure598. In other embodiments, different techniques may be employed toremove the rollers 596 from their respective roller housing structures598, such as via tools, a handle disposed on the roller 596, and othertechniques. As noted above, the roller 596 may extend beyond certainfeatures of the roller housing structure 598, such as beyond curvedinner surfaces of the roller housing structure 598 that grip the roller596, which may facilitate extraction of the roller 596 from the rollerhousing structure 598 by providing access to ends of the roller 596 forgripping purposes.

FIG. 54 is a cross-sectional schematic view of the interconnect assembly128 having the roller 596 and the roller housing structure 598.Specifically, the illustrated embodiment shows the roller 596 beingpositioned in the roller housing structure 598 to secure the tabelectrodes 129 in electrical communication. Prior to insertion of theroller 596, the first and second tab electrodes 129 may be pre-shaped toconform at least partially to the roller housing structure 598, as shownby arrows 604. More specifically, the tab electrodes 129 may be broughttoward the roller housing structure 598 and bent around respective outeredges of the roller housing structure 598. The tab electrodes 129 may bepre-shaped around the roller housing structure 598 such that respectivedistal ends (e.g., free ends) of the tab electrodes 129 are disposed inthe opening 600 defined by the roller housing structure 598. In otherwords, the tab electrodes 129 terminate in the opening 600 of the rollerhousing 598. In other embodiments, the tab electrodes 129 may bethreaded into an interior portion of the roller housing structure 598and conformed along interior surfaces until distal ends of the tabelectrodes 129 terminate outside of the opening 600, as illustrated inFIG. 55. By positioning the tab electrodes as shown in FIG. 55, materialused for the tab electrodes 129 may be conserved relative to otherembodiments.

The roller housing structure 598 may be specifically shaped to receivethe tab electrodes 129 in the conformed orientation about the rollerhousing structure 598 and disposed in the opening 600. For example, theroller housing structure 598 may be located near the battery cells 116in a direction of the positive Z axis 40 relative to the battery cells116. The tab electrodes 129 may extend from the battery cells 116 in thepositive Z direction toward the roller housing structure 598, and may beconformed around the outer edges of the roller housing structure 598 andtoward the opening 600. The opening 600 may be defined along the side ofthe roller housing structure 598 that faces the positive Z direction.The tab electrodes 129 may be wrapped about the roller housing structuresuch that the ends of the tab electrodes 129 extend into the opening600, in the negative Z direction. The roller 596 may be inserted, asshown by an arrow 606, into the opening 600 to secure the tab electrodes129 between the roller housing structure 598 and the roller 596 disposedin the opening 600. The roller 596 may include a substantiallycylindrical bar aligned axially with the X axis 44, and the roller 596may be inserted into the roller housing structure 598 in the negative Zdirection. Since the roller 596 is inserted in the same direction (e.g.,negative Z direction) as the tab electrodes 129 disposed in the opening600, the tab electrodes 129 may be pushed further into the opening 600and against the roller housing structure 598. This arrangement avoidsdisplacement and wrinkling of the tab electrodes 129 during insertion ofthe roller 129. Further, this may increase the surface area of the tabelectrodes 129 disposed between and in contact with the roller 596 andthe roller housing structure 598, thereby enabling an increasedelectrical connection between the tab electrodes 129.

As discussed above, one or both of the roller 596 and the roller housingstructure 598 may be conductive to facilitate electrically coupling thetab electrodes 129. In the illustrated embodiment, the tab electrodes129 conform only partially along a surface of the roller housingstructure 598 that defines the opening 600. However, in otherembodiments, the tab electrodes 129 may extend far enough within theopening 600 to wrap around opposite sides of the roller 596 until thetab electrodes 129 are touching each other. In such instances, theroller housing structure 598 and/or the roller 596 may not be conductiveat all and may essentially be used as a support for establishing anelectrical connection between the tab electrodes 129. In suchembodiments, the tab electrodes 129 themselves may be pre-shaped aroundthe roller housing structure 598 until they are overlapping with respectto each other in the opening 600. Then, the roller 596 may be positionedin the opening 600 defined by the roller housing structure 598 to securethe tab electrodes 129 in direct contact with each other for providingthe electrical connection. In still other embodiments, the tabelectrodes 129 may be in contact with each other, and the roller 596 maybe conductive, so that the electrical connection is established via theroller 596.

The opening 600 defined by the roller housing structure 598 may includea substantially semi-circular opening configured to receive the roller596. That is, the roller housing structure 598 may include asubstantially semi-circular cross section that defines the opening 600,and this cross section may partially trace a circle. The roller 596 mayinclude a substantially cylindrical roller or bar configured to bereceived into the substantially semi-circular opening 600. In someembodiments, a diameter of the circle partially traced by the rollerhousing structure 598 (e.g., a diameter of the opening 600) may beapproximately the same size, or slightly smaller than, an outer diameterof the roller 596 configured to be disposed therein. The roller housingstructure 598 may be configured to elastically deform to receive andhold the roller 596 in the opening 600.

In the illustrated embodiment, the roller housing structure 598 includestwo separate structures 608 (e.g., first and second structures 598 thatare components of the roller housing structure 598), and these twostructures 608 are separated by a space 610 to define the opening 600.The two structures 608 may be coupled together via the frame pieces 526of the cell interconnect board 130. Each structure 608 may be configuredto receive a respective tab electrode 129 in a conforming orientationwith respect to the structure 608 such that the tab electrode 129 isdisposed in the opening 600 defined by the roller housing structure 598.

In the illustrated embodiment, the structures 608 may be relativelyrigid structures for providing structural support for the connection ofthe tab electrodes 129. The space 610 (e.g., separation) between thestructures 608 may allow the structures 608 to be elastically deformedaway from each other slightly to receive the roller 596 as the roller596 is inserted into the opening 600. This deformation of the structures608 away from each other may expand the opening 600 to receive and holdthe roller 596 in the opening 600. As the roller 596 is pushed into theopening 600, the tab electrodes 129 may become more tightly conformedaround the structures 608 as the roller 596 urges the ends of the tabelectrodes 129 further into the opening 600.

In the illustrated embodiment, the structures 608 have a specific shapeto facilitate conforming of the tab electrodes 129 about the rollerhousing structure 598 and securing of the tab electrodes 129 in theopening 600. More specifically, each structure 608 includes an interiorprong 612 and an exterior prong 614 coupled together and extendingtoward the battery cells 116. Each structure 608 is configured toreceive a respective tab electrode 129 in a conforming orientation aboutan outer edge of the respective exterior prong 614. A connecting portion616 disposed between the interior and exterior prongs 612 and 614 mayinclude rounded corners to provide a relatively smooth transition forthe tab electrode 129 that is wrapped from the exterior prong 614 aroundthe interior prong 612. The pair of tab electrodes 129 may be conformedaround the exterior prongs 614 of the respective structures 608, andextend into the opening 600 defined by the interior prongs 612. Theinterior prongs 612 may be curved, as illustrated, to define thesubstantially semi-circular opening 600 for receiving the roller 596into the roller housing structure 598. The interior prongs 612 may beconfigured to elastically deform away from each other to receive theroller 596 when the roller 596 is disposed in the opening 600.

It should be noted that other embodiments of the interconnect assembly128 may utilize other shapes of roller housing structures 598 to receivethe rollers 596 for securing the tab electrodes 129 in electricalconnection. For example, in some embodiments, the roller housingstructure 598 may include a single-piece structure. This may be similarto the illustrated embodiment, but with the interior prongs 612 combinedto form a single piece that defines the substantially semi-circularopening 600 along the outward facing side of the roller housingstructure 598. In such embodiments, since there is no space 610 todefine the opening 600, the roller housing structure 598 may be madefrom relatively flexible materials. This may allow the roller housingstructure 598 to deform slightly, expanding the opening 600 to receiveand capture the inserted roller 596. Such embodiments may beparticularly useful for connecting the tab electrodes 129 in directcontact with each other.

Other variations of the roller 596 may be possible as well. For example,as illustrated in FIG. 56, the roller 596 may include a substantiallycylindrical bar 618 that is hollow. This may reduce an overall weight ofthe battery module 22, as compared to a solid cylindrical bar. In otherembodiments, one or both of the roller 596 and the roller housingstructure 598 may include teeth for gripping the tab electrodes 129between the roller 596 and the roller housing structure 598. Asillustrated in FIG. 57, for example, the roller 596 may be equipped withteeth 620 disposed along an outer surface of the substantiallycylindrical roller 596. Similarly, the roller housing structure 598 mayinclude teeth 620 disposed along an inner surface (e.g., circumference)of the roller housing structure 598 that defines the opening 600. In theillustrated embodiment, for example, the interior prongs 612 of thestructures 608 that make up the roller housing structure 598 includeteeth 620 along the inner facing sides of the interior prongs 612. Theteeth 620 may be included on portions of the roller housing structure598 configured to directly contact the tab electrodes 129 being heldbetween the roller 596 and the roller housing structure 598. In otherembodiments, the teeth 620 may be included on every surface of theroller housing structure 598 that is configured to receive the conformedtab electrodes 129. The teeth 620 may include ridges, bumps, detents,layers of relatively coarse material, or any other component that mayincrease the friction for maintaining the tab electrodes 129 in theelectrically coupled position between the roller 596 and the rollerhousing structure 598. Other embodiments of the interconnect assembly128 may utilize different types of rollers 596 and/or roller housingstructures 598 than those shown in the present disclosure.

One or more of the disclosed embodiments, alone or in combination, mayprovide one or more technical effects useful in the assembly andmaintenance of battery modules with a number of battery cells arrangedin a stacked orientation relative to each other. For example, certainembodiments of the present approach may enable improved interconnectionsbetween tab electrodes extending from the different battery cells. Byspecific example, conforming the tab electrodes around a roller housingstructure and securing the tab electrodes in electrical communicationwith each other via a roller disposed in the roller housing structure,as set forth above, may enable easier connections and disconnections ofthe battery cells, compared to battery interconnect assemblies that relyon relatively permanent connection methods, such as laser welding orfastening elements (e.g., screws). The presently disclosed interconnectassembly provides a simple mechanical roller and roller housingstructure that facilitates electrical coupling of the tab electrodes.Such rollers and roller housing structures may be relatively easy tomanufacture. The roller housing structure may includes features (e.g.,prongs) that facilitate conforming of the tab electrodes around theroller housing structure such that, when the roller is inserted into anopening defined by the roller housing structure, the tab electrodes areforced into a more direct contact with the outer circumference of theroller. The roller may be manually inserted into and removed from theroller housing structure as desired, making the disclosed interconnectassembly more versatile than laser welding and other existing techniquesfor the disconnection, removal, or replacement of individual batterycells in the battery module. As such, the interconnection of batterycells via a roller and roller housing structure may generally enable abattery module with a more simple assembly and with individuallyreplaceable battery cells. The technical effects and technical problemsin the specification are exemplary and are not limiting. It should benoted that the embodiments described in the specification may have othertechnical effects and can solve other technical problems.

Printed Circuit Board Interconnect for Cells in a Battery System

As mentioned above, the cell interconnect board 130 provides structuralsupport for the interconnection of the battery cells 116 and a number ofsensors 132. The cell interconnect board 130 includes slots 134, one foreach pair of battery cells 116. As illustrated in FIG. 58, positionedover each slot 134 is an interconnect 622 which allows for the physicalconnection of the battery cells 116 and the cell interconnect board 130.In the embodiment illustrated in FIG. 58, the interconnects 622 areelectrically conductive bars coupled to the cell interconnect board 130on the exterior-facing side facing away from the battery cells 116.However, the interconnects 622 may alternatively be placed on theinterior side of cell interconnect board 130 facing the battery cells116. The tab electrodes 129 of the battery cells 116 can be secured andelectrically connected to an interconnect 622 using one or moreinterconnection devices 138, as discussed with respect to FIGS. 40-57.

Because the cell interconnect board 130 may be manufactured from aprinted circuit board, each of the interconnects 622 may be electricallycoupled via traces 624 to sensors 132, which are used to monitor variousmetrics associated with the state of the battery cells 116. For example,one or more voltage sensors 132 a, which may be located on theexterior-facing side of the cell interconnect board 130, may be used tomonitor the output voltage of a pair of battery cells 116.Alternatively, the voltage sensors 132 a may be located on theinterior-facing side of the cell interconnect board 130 or within thePCB if the PCB is a multilayer board. The sensors 132 may be connectedto one or more terminal blocks 626, which connect to the BCM 72 toprovide the associated data.

Other sensors 132, such as temperature sensors 132 b or pressure sensors132 c, may be also located on the cell interconnect board 130, as shownin FIG. 59. Unlike voltage sensors 132 a, which monitor a specificoutput of the battery cells 116, temperature sensors 132 b and pressuresensors 132 c monitor the environment of battery cells 116. As such,temperature sensors 132 b and pressure sensors 132 c may be placed onthe interior-facing side of the cell interconnect board 130, closest tothe battery cells 116. The temperature sensors 132 b and pressuresensors 132 c may not be electrically coupled to the interconnects 622,as shown in FIG. 59. According to other embodiments, the temperaturesensors 132 b and pressure sensors 132 c may be electrically coupled tothe interconnects 622. In such a case, the temperature sensors 132 b maybe electrically isolated. These sensors 132 may then be connected to oneor more terminal blocks 626. The terminal block 626 connects to the BCM72 to provide the associated data.

An alternative embodiment of battery cells 116 may include a cellinterconnect board attachment 628 and an interconnect portion 630. A tabelectrode 129 of a battery cell 116 may include a slit 632 that dividesthe tab electrode 129 into a cell interconnect board attachment 628 andan interconnect portion 630, as shown in FIG. 60. The interconnectportion 630 may be coupled to an interconnect 622 as described above.The cell interconnect board attachment 628 may be directly coupled to asensor pad 634 on the cell interconnect board 130 by any appropriatetechnique, such as a weld, solder, or electrically conductive adhesive.In this embodiment, any sensors 132, such as voltage sensor 132 a, thatwould be electrically connected to interconnects 622, are insteadelectrically connected to cell interconnect board attachments 628.Alternatively, the cell interconnect board 130 used in this embodimentmay not be made of a PCB material, but instead may include a PCB coupledto the cell interconnect board 130 in order to access the dataassociated with the sensors 132.

In some embodiments, the battery cells 116 may all be connected inseries to produce a first output voltage (e.g., 48 V), as shown in FIG.61. The interconnects 622 at the top and bottom of the cell interconnectboard 130 are connected via address voltage sense lines 640 to aterminal block 626. This connection allows terminal block 626 to providethe first output voltage associated with the series combination of allof the battery cells 116.

In some cases, the first output voltage provided by the seriescombination of all battery cells 116 may exceed the output voltagerequirements of the battery module 22. In such cases, the battery cells116 may be divided into battery cell groups 638, each of which providesa second output voltage (e.g., 12 V) that matches the lower outputvoltage requirement of the battery module 22, as shown by FIG. 62. Eachbattery cell group 638 includes one or more battery cells 116 connectedin parallel via the cell interconnect board 130 and bus bars 636. Eachbattery cell group 638 is then connected via bus bars to the terminalblock 626.

One or more of the disclosed embodiments, alone or in combination, mayprovide one or more technical effects useful for electrically connectingand securing stacked battery cells within a battery module. For example,certain embodiments may enable greater structural support for stackedbattery cells. Certain embodiments may also allow for improvedelectrical connections between individual battery cells and batterycells and sensors. For example, the present cell interconnect boardcontains interconnects that provide a rigid structure to which batterycells may be directly coupled. Battery cells can be coupled to theinterconnects with devices that are easy to attach and remove. Such astructure allows for the battery cells to be packaged in a mannersimilar to existing technology without the permanent assembly solutions,such as welding, which are commonly found in existing technology.Additionally, the present cell interconnect board also contains aprinted circuit board which electrically connects the battery cells tovarious sensors. As such, the present cell interconnect board does notrequire a separate printed circuit board and connection elements coupledto the cell structure to provide the electrical connections betweenbattery cells and sensor circuitry. The technical effects and technicalproblems in the specification are exemplary and are not limiting. Itshould be noted that the embodiments described in the specification mayhave other technical effects and can solve other technical problems.

DC-to-DC Converter for Batteries Having Multiple Positive Terminals

As mentioned above, the battery module 22 can be configured to providetwo or more output voltages using three or more terminals. For example,the battery module 22 can provide a first output voltage (e.g., 48 V or130 V) to high power components such as electric power steering, activesuspension, BAS 29, and HVAC system 32. The battery module 22 can alsoprovide a second output voltage (e.g., 12 V) to other components such asinterior lights, entertainment systems, and door locks. By using abattery module 22 that provides two or more voltages, the variouscomponents of the mHEV 10 can be coupled to the battery module 22 suchthat they receive an efficient operating voltage given theirrequirements.

The battery module 22 may use one or more DC-to-DC converters 76 toprovide the two output voltages from the power assembly 84. A DC-to-DCconverter 76 may be a traditional buck, boost, or buck-boost converter,for example, that receives the output voltage across the series ofbattery cells 116 as an input and produces the second output voltage, asshown in the block diagram of FIG. 63. As such, the battery module 22 isconfigured to simultaneously provide two output voltages over threeterminals.

A traditional DC-to-DC converter 76 may receive the output voltageacross the series of battery cells 116, discharging all of the batterycells 116. Alternatively, the DC-to-DC converter 76 may be a switchingnetwork that selectively chooses one or more battery cell groups 638 toprovide the second output voltage, as shown in the block diagram of FIG.64. Each battery cell group 638 includes a subset of all of the batterycells 116. By selecting a subset of the battery cells 116, the switchingnetwork may reduce the overall rate of discharge for the battery cells116. Although FIG. 56 depicts a configuration of 13 battery cells 116,wherein each battery cell 113 is also a battery cell group 638, itshould be appreciated that a battery cell group 638 may include anynumber of battery cells 116, such as one, two, or four battery cells116.

The switching network DC-to-DC converter 76 may include a voltagemultiplexor 670 and a ground multiplexor 672, both of which receive aninput from each battery cell group 638. The voltage multiplexor 670 andground multiplexor 672 select the battery cell groups 638 which willprovide the second output voltage.

However, the voltage multiplexor 670 and ground multiplexor 672 receivethe same input from each battery cell group 638. As mentioned above, thevoltage multiplexor 670 and ground multiplexor 672 only select whichbattery cell groups 638 are used to provide the second output voltage.As such, the voltage drop between the outputs of the voltage multiplexor670 and ground multiplexor 672 may or may not equal the desired secondoutput voltage.

To ensure that the second output voltage is produced, the voltagesignals generated by the voltage multiplexor 670 and ground multiplexor672 may then pass through an isolation DC-to-DC converter 674. Theisolation DC-to-DC converter 674 may be a buck, boost, or buck-boostconverter. The isolation DC-to-DC converter 674 accepts the output ofthe voltage multiplexor 670 and ground multiplexor 672 as inputs andproduces a second output voltage signal and a ground signal. Theswitching network DC-to-DC converter 76 may also include at least onefilter or clamping circuit (not shown) to reduce or eliminateinterruptions in power or spikes in output voltage or current.

In such cases, the BCM 72 may control the DC-to-DC converter 76, asshown in FIG. 65. For example, U.S. Provisional Applications No.61/746,818, filed on Dec. 28, 2012, and No. 61/800,103, filed on Mar.15, 2013, both disclose a battery system containing a switching networkthat connects one or more groups of battery cells to a secondary voltageterminal, and both of these applications are incorporated by referencein their entireties for all purposes. The term “switching network” isintended to not be limiting but to include any devices that are capableof being selectively changed between an electrically conductive state toa nonconductive state, such as silicon controlled rectifiers, powertransistors, relay switches or any other like devices. The BMMScontrolling the switching network determines which groups of batterycells to connect, based on the measured state of charge for the groupsof battery cells and the desired output of the DC-to-DC converter 76.The BMMS may have a predetermined order for connecting groups, and maydisconnect a group when the charge has declined to a preselected minimumstate of charge limit.

Both the traditional DC-to-DC converter 76 and the switching networkDC-to-DC converter 76 may electrically connect via one or more terminalblocks 626 to the interconnects 622 located on the cell interconnectboards 130. Each of the pair of cell interconnect boards 130 may includea terminal block 626. In an embodiment employing a traditional DC-to-DCconverter, the top interconnect 622 on one cell interconnect board 130may be electrically coupled to the terminal block 626, as shown in FIG.58. The bottom interconnect 622 on the other cell interconnect board 130would be electrically coupled to the terminal block 626. The traditionalDC-to-DC converter 76 may then be connected to the terminal block 626located on both of the cell interconnect boards 130 such that itreceives as an input the output voltage provided by a series combinationof the battery cells 116.

In an embodiment employing a switching network DC-to-DC converter, thetop and bottom interconnects 622 of each battery cell group 638 may beelectrically coupled to the terminal block 626, as shown in FIG. 59. Aterminal block 627, located on the top plate 100, may be electricallycoupled to the terminal block 626 located on both of the cellinterconnect boards 130 to consolidate the inputs from the battery cellgroups 638. The switching network DC-to-DC converter 76 may then beconnected to the terminal block 627 to receive the inputs from each ofthe battery cell groups 638.

Alternatively, a battery module 22 may contain four or more terminals,two of which may produce an equal amount of voltage, as shown in FIG.68. For example, the battery module 22 may provide a first outputvoltage (e.g. 48 V or 130 V) using a first terminal, while the secondand third terminals each produce a second output voltage (e.g., 12 V).One of the terminals producing the second output voltage may be capableof handling high loads such as cranking a cold engine. The otherterminal producing the second output voltage may be adapted to handlelow power loads. Components of the mHEV 10 can be coupled to either thesecond or third terminal based on their power requirements. BothDC-to-DC converters 76 may be coupled to the top of the battery module22, as shown in FIG. 69, or one of the DC-to-DC converters 76 may becoupled to the top plate 100 and top portion 54 while another DC-to-DCconverter 76 may be coupled to the exterior side of a cell interconnectboard 130, as shown in FIG. 70. If one or more DC-to-DC converters 76are used exclusively for high power loads, then those DC-to-DCconverters 76 may also be coupled to a cooling system for heatdissipation.

In another embodiment, both a traditional DC-to-DC converter 76 and aswitching network DC-to-DC converter 76 may be used in a four-terminalbattery module 22, as shown in the block diagram of FIG. 71. Thetraditional DC-to-DC converter 76 may be used exclusively for high powerloads, and the switching network DC-to-DC converter 76 may be usedexclusively for low power loads. Using a switching network DC-to-DCconverter 76 with only low power loads may mitigate effects of powerswitching, such as interruption of power, spikes in output current orvoltage, and arcing. The switching network DC-to-DC converter 76 mayalso perform as a separate stable voltage network, providing an activecharge balancing function during vehicle operation and/or for key-offload support.

One or more of the disclosed embodiments, alone or in combination, mayprovide one or more technical effects useful for providing multipleoutput voltages from a single battery module. Certain embodiments mayenable improved placement of components to reduce the overall size ofthe battery modules. Certain embodiments may also provide multipleoutput voltages, each of which can be used exclusively for high or lowpower loads. For example, the present approach of placing a DC-to-DCconverter on the lid or side of a battery module allows the batterymodule to retain the overall shape of the battery modules found inexisting lead acid technology. Using one or more DC-to-DC converters ora DC-to-DC converter in conjunction with a switching network also allowsvarious terminals to be configured for either high or low power loads.The technical effects and technical problems in the specification areexemplary and are not limiting. It should be noted that the embodimentsdescribed in the specification may have other technical effects and cansolve other technical problems.

Pouch Frame with Integral Circuitry for Battery Module

As mentioned above, the battery module 22 may include two cellinterconnect boards 130 with interconnects 622. Each battery cellassembly 114 may include a frame 118 and a battery cell 116, which hastab electrode 129. The tab electrodes 129 of a pair of battery cells 116are secured to each interconnect 622 using one or more interconnectiondevices 138.

An alternative embodiment of battery cell assembly 114 includes abattery cell 116 that does not have tab electrodes 129. Instead, theframe 118 includes one or more female connectors 700 and one or moremale connectors 702, as shown in FIG. 72. The female connectors 700 andmale connectors 702 couple together to electrically connect batterycells 116 to one another, thus eliminating separate cell interconnectboards 130 and other associated circuitry.

The frame 118 may be split into a top frame portion 118 a and a bottomframe portion 118 b. The top frame portion 118 a contains one or morefemale connectors 700 and the bottom frame 118 contains one or more maleconnectors 702. Both the top frame portion 118 a and the bottom frameportion 118 b also contain an electrically conductive tab 704 and 705,respectively, located on an interior side. The electrically conductivetabs 704 and 705 are connected to the female connectors 700 and maleconnectors 702, respectively, via traces 624 in the frame 118.

The battery cell 116 includes two electrically conductive contact plates706 and 707, located on the battery cell 116 such that they align withthe electrically conductive tabs 704 on the frame 118. The electricallyconductive contact plates 706 and 707 may be coupled to the positive andnegative terminals, respectively, of the battery cell 116, or viceversa. When assembled as in FIG. 73, the electrically conductive tabs704 and 705 are inserted such that they contact and electrically connectto the electrically conductive contact plates 706 and 707. The batterycell 116 is then sealed so that the electrically conductive contact tabs704 and 705 and the electrically conductive contact plates 706 and 707are securely coupled together, creating an electrical connection betweenbattery cell 116 and the connectors 700 and 702. The top frame portion118 a and bottom frame portion 118 b may be coupled to one another usingbolts 140, for example.

To vent any excessive amount of gas in the battery cells 116, the topframe portion 118 a may also include pressure points 708, which areportions of the frame 118 a that are structurally weaker than the restof top frame portion 118 a. When the pressure of the battery cell 116exceeds a threshold, the pressure points 708 of frame 118 break open.This allows the battery cell assembly 114 to vent pressurized fluids ordissipate heat.

The top frame portion 118 a contains one or more female connectors 700and an electrically conductive tab 704, as shown in FIG. 74, and thebottom frame portion 118 b contains one or more connectors 702 and anelectrically conductive tab 705, as shown in FIG. 75. While the femaleconnectors 700 and male connectors 702 may be placed in the center onone side of top frame portion 118 a or bottom frame portion 118 b, theymay be located on any portion of frame 118. The female connectors 700and male connectors 702 may also be used alone or in conjunction withany number of registration features 121 to couple the frames 118 to oneanother.

To form a power assembly 84, the battery cell assemblies 114 are stackedon top of one another using female connectors 700 and male connectors702, as shown in FIG. 76. The positive electrodes of battery cells 116are coupled to the electrically conductive contact tab 704 on top frameportion 118 a and electrically connect to female connectors 700. Thenegative electrodes of battery cells 116 are coupled to the electricallyconductive contact tab 705 on bottom frame portion 118 b andelectrically connect to male connectors 702. The female connectors 700and male connectors 702 couple together to electrically connect thebattery cells 116 in series. Stacking the battery cell assemblies 114 inthe manner shown in FIG. 76 allows for simple assembly, maintenance, andrepair of the power assembly 84. Also, as mentioned above, the cellinterconnect boards 130 and circuitry that connect the battery cells 116to one another may not be used.

The frame 118 may be located within the battery cell 116 rather thanoutside, as shown in FIG. 77. In this embodiment, frame 118 is a onepiece structure that includes two electrically conductive contact tabs704, one or more female connectors 700, and one or more male connectors702. The frame 118 surrounds the active materials portion 710 of batterycell 116, and the electrically conductive contact tabs 704 and 705directly contact the electrically conductive contact plates 706 and 707,respectively. The upper pouch layer 710 and lower pouch layer 712 ofbattery cell 116 may then be welded together around frame 118. Upperpouch layer 710 and lower pouch layer 712 may include openings to allowfor access to female connectors 700 and male connectors 702.

To monitor the output or state of battery cells 116, sensors 132 may becoupled to frame 118. The sensors 132 that monitor the environmentsurrounding the battery cells 116, such as temperature sensors 132 b,may be coupled to the interior side of top frame portion 118 a, as shownin FIG. 78A. So that they are close to the battery cells 116. Othersensors 132 that monitor the output of battery cells 116, such asvoltage sensors 132 a, may be coupled to the exterior side of bottomframe portion 118 b, as shown in FIG. 78B. The sensors 132 that monitorthe output of battery cells 116 may be coupled to either the exterior orinterior side of frame 118 and are connected via traces 624 to anelectrically conductive tab 704. The sensors 132 may be located on anyside of either the top frame portion 118 a or bottom frame portion 118b.

Certain sensors 132 may be located on a particular side of frame 118,such that when the battery cell assemblies 114 are stacked, the sensors132 on a side alternate, as shown in FIG. 79. An alternative embodimentof cell interconnect board 130, as shown in FIG. 80, may contain aseries of connectors that attach to the connectors associated withsensors 132 on frames 118. These connections allow data provided bysensors 132 to be sent to the BCM 72 via one or more terminal blocks 626attached to cell interconnect board 130.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful for reducing the amount ofpackaging for a battery module. Specifically, certain embodiments mayreduce the amount of components and connection used to electricallyconnect individual battery cells. Certain embodiments may also reducethe amount of components and connections used to electrically connectbattery cells to various sensors. These frames can also includeconnectors that allow frames to electrically connect to one another,eliminating a separate printed circuit board to perform the same task.The connectors can be designed such that assembly and maintenance of astack of battery cells is simpler than that of current solutions, whichuse permanent techniques such as welding. Additionally, the presentframes can include various sensors, eliminating a separate printedcircuit board to connect battery cells to various sensors. The technicaleffects and technical problems in the specification are exemplary andare not limiting. It should be noted that the embodiments described inthe specification may have other technical effects and can solve othertechnical problems.

Remanufacturing Methods for Battery Module

Given the modular nature of the battery modules 22 discussed herein, aswell as the different embodiments of various sections of the batterymodules 22, which may be interchanged in any combination, presentembodiments also relate to the remanufacturing of at least a portion ofthe battery modules 22. For example, any one or a combination of thebattery modules 22 discussed above may be remanufactured to produce aremanufactured version of the battery module 22 including both new andused components, where the new components and the used components may beselected from any one or a combination of the embodiments describedabove. As defined herein, a “new” component is intended to denote acomponent that has not been used as a part of the particular batterymodule 22 being remanufactured, i.e., it is new with respect to theparticular remanufactured battery module 22. In this way, a newcomponent integrated into an embodiment of the battery module 22 (e.g.,as a vehicular battery module) in accordance with present embodimentsmay previously have been used in another context, for example, a homebattery, a computer battery, or another vehicular battery, or even anentirely different implementation (e.g., not a battery). Indeed, the newcomponents may be remanufactured components themselves obtained from adifferent device. Furthermore, based on this definition, a new componentmay also denote a component that has never been used in anyimplementation, other than those implementations typically occurring asa part of a manufacturing process (e.g., as in testing for qualitycontrol). On the other hand, a “used” component, as defined herein, isintended to denote a component that has been used as a part of theparticular battery module 22 being remanufactured. Therefore, acomponent that is removed from the battery module 22, and issubsequently re-fastened, re-attached, or otherwise re-positioned to orwithin the battery module 22 without incorporating a new component,would be referred to as a used component. In certain embodiments, theused components may be processed to restore their appearance or feel(i.e., properties that have no effect on the efficacy of the particularcomponent). Such processing may be referred to as refurbishment.

The particular components of the remanufactured battery modules that arenew or used are not particularly limited. However, an entity thatperforms the remanufacturing of the battery module 22 may have certainconsiderations (e.g., cost, availability of parts, time available forremanufacture) that may affect which components may be new componentsand which are used components, and the particular manner in which thebattery module 22 is remanufactured. In certain embodiments of thepresent disclosure, for example, where the time available forremanufacturing an embodiment of the battery module 22 may be ofconcern, a rapid battery module remanufacturing process may includeexposing, removing, and altogether replacing the power assembly 84 ofthe battery module 22 with a new power assembly 84.

On the other hand, in certain embodiments, such as where time is less ofa concern, the remanufacturing process may include remanufacturingindividual battery cell assemblies 114. Such remanufacturing mayinclude, with respect to at least one battery cell assembly 114,replacing the battery cell 116, one or more of the gap pads 115,122, theframe 118, the heat fin 112, the phase change material layer 124, or anycombination thereof, with a new battery cell 116 and/or other respectivelayer. The used portions of the battery cell assemblies 114, along withother used portions of the battery module 22, when retained, may,additionally or alternatively, be refurbished in a manner that enhancesthe appearance, but not the functionality, of the remanufactured batterymodule 22. As an example, one or more of the frames 118, one or more ofthe heat fins 112, or a combination thereof, may be polished.

In addition to or as an alternative to remanufacturing the powerassembly 84, certain used electrical components of the battery module 22may be replaced with new respective electrical components. For example,the terminals 24, 26, 30, DC-DC converter 76, and/or portions (or all)of the interconnect assemblies 128 may be replaced. Further, in certainembodiments, these and other electrical components may be repaired, suchas by re-soldering electrical connections, re-plating conductive metals(e.g., electrical connectors), and/or reinforcing the structuralsupports for the electrical components (e.g., the cell interconnectboard 130).

Furthermore, the present disclosure is not limited to remanufacturingthe battery modules 22 described herein to re-produce the same type ofbattery module 22. Indeed, all or a portion of the battery modules 22described herein may be remanufactured in a way that repurposes thebattery module 22. For example, the battery modules 22 may beremanufactured to include different types of battery cells 116, toinclude different circuit arrangements such that the battery module 22provides different types of power (e.g., 12 volts versus 48 volts), orany other arrangement that enables its use for the provision of power ina different manner. In some embodiments, such repurposing may beaccomplished by replacing the used battery cells 116 with new batterycells 116 that have different voltages, by re-connecting certain of thebattery cells 116 in parallel rather than only in series, and/or bychanging the battery module's interfaces (e.g., the type and/or numberof terminals 24, 26, 30).

The remanufacturing processes discussed herein may be performed by anumber of different operators at varying locations, such as at amanufacturing plant, a service center, an automotive store, or atanother facility, such as a vehicle servicing facility (e.g., a servicegarage). FIG. 81 is a process flow diagram of an embodiment of ahigh-level remanufacturing process 760 that may be performed at any oneor a combination of the locations noted above. The process 760 mayinclude, as depicted, obtaining (block 762) a used version of thebattery module 22. For instance, the battery module 22 may have beenused in a vehicle, or in another setting. The acts according to block762 may include receiving the battery module 22, such as via shipment,removing the battery module 22 from a vehicle, home, or other location,or otherwise isolating the battery module 22 from other periphery towhich the battery module 22 may have been connected. For example,referring to the embodiment depicted in FIG. 4, in one embodiment theacts according to block 762 may include disconnecting the battery module22 from the starter motor 28, the HVAC 32, the VCM 36, or anycombination thereof.

Before, during, or after obtaining the battery module 22 in accordancewith block 762, the used battery module 22 may be inspected and/ortested (block 764). The particular manner in which the battery module 22is inspected and/or tested may at least partially depend on the locationwhere the battery module 22 is remanufactured and the extent to whichthe battery module 22 is remanufactured. For example, in certainsettings, a technician or other operator performing the remanufacturingprocess may not have ready access to certain types of electrical testingequipment. In such a setting, the remanufacturing operator may rely moreon a visual inspection of the used battery module 22 and its associatedcomponents, rather than on equipment having interfaces capable ofobtaining accurate readings from the battery module 22. By way ofexample, the acts according to block 764 in such situations may includevisually inspecting various components for wear resulting fromvibration, thermal fluctuations, or the like (e.g., by observing breaksin electrical connections, wear or crazing of polymeric surfaces, bendsor other deformities in metallic parts).

In other settings, more sophisticated testing may be performed inaddition to or in lieu of visual inspections. For example, in someembodiments, such as when individual battery cells 116 will be replaced,an operator may perform electrical measurements on one or more of theindividual battery cells 116 to determine whether, or to what extent,their performance has degraded. For example, the electrical measurementsmay determine that one or more of the battery cells 116 are notproducing electrical energy at a desired voltage and/or current. Similartesting may be performed on the entire power assembly 84.

In certain embodiments, the phase change material layers 124 may betested. For example, the phase change material layers 124 may besubjected to physical analyses so as to determine whether the phasechange material disposed therein is operating within a desired set ofparameters (e.g., within a desired temperature range). Additionally oralternatively, chemical analyses may be performed on the phase changematerial layers 124 to determine, for example, a concentration of thephase change material within the phase change material layers 124.

Additionally or alternatively, other portions of the battery module 22may be tested and/or inspected in accordance with block 764. Forexample, the electrical components of the interconnect assemblies 128may be inspected (e.g., for metal deterioration) and tested. Because thecell interconnect board 130 (e.g., a ladder structure including theframe pieces 526) of the interconnect assemblies 128 may, in someembodiments, at least partially structurally support the power assembly84, the cell interconnect board 130 may be inspected for structuralintegrity (e.g., for cracks, crazing, and/or warping). The terminals 24,26, 30 may also be inspected, for example for metal deterioration (e.g.,abrasion, scraping, oxidation). Additionally or alternatively, theconductivity of the terminals 24, 26, 30 may be verified using suitableelectrical tests. The DC-DC converter 76 may also be tested to determinewhether it is capable of maintaining quality operation in the context ofa remanufactured battery module.

After inspection and/or testing in accordance with block 764, theprocess 760 includes determining (query 766) whether it is appropriateto remanufacture the battery module 22. In embodiments where it is notappropriate to remanufacture the battery module 22, the battery module22 may be discarded (block 768), such as by recycling the various partsof the battery module 22 for use in other implementations. By way ofnon-limiting example, the battery module 22 may not be remanufactured inembodiments where the battery module 22 does not include portions thatmay be retained in a remanufactured version of the battery module 22.For instance, the battery module 22 may have broken parts, or the partsmay be so severely worn that they do not pass certain quality criteria.Indeed, in some embodiments, depending on how much of the battery module22 may be retained, it may not be cost-effective to remanufacture thebattery module 22 and the battery module 22 may be discarded.

On the other hand, in embodiments where the battery module 22 may beappropriately remanufactured, the battery module 22 may be processedaccording to a desired remanufacturing process (block 770). For example,as noted above and as discussed in further detail below, at least aportion of the power assembly 84, at least a portion of the interconnectassemblies 128, at least a portion of the side assemblies 106, at leasta portion of the battery control assembly 70, or any combinationthereof, may be remanufactured in accordance with present embodiments.Indeed, any one or a combination of the embodiments of various portionsof the battery module 22 discussed above may be remanufactured to havethe configuration of any one or a combination of the other embodimentsdiscussed above. That is, the present disclosure is intended toencompass embodiments of the battery module 22 having any permutationsand any combinations of the components described above with respect topresent embodiments, whether in new or remanufactured contexts.Therefore, while described above as particular embodiments of thebattery module 22, the present disclosure encompasses any and allcombinations of these embodiments being used in a remanufactured versionof the battery module 22.

After the appropriate remanufacturing process has been performed inaccordance with block 770, the remanufactured version of the batterymodule 22 may be tested (block 772) to ensure compliance with variousstandards associated with the particular type of battery module 22 beingremanufactured. For instance, in embodiments where the battery module 22is to be used in a vehicle (e.g., the xEV 10 of FIG. 1), the testing maybe used to ensure compliance with various vehicular standards.

After the battery module 22 is tested according to the acts representedby block 772, the battery module 22 may be packaged (block 774). Forexample, the cover 59 may be secured to the remainder of the batterymodule 22 (if not done at an earlier process stage). In certainembodiments, the remanufactured battery module 22 may be packaged in anappropriate container and shipped and/or provided to a desired location(e.g., a store and/or a servicing facility or consumer). In embodimentswhere the battery module 22 is remanufactured in a servicing facility(e.g., a vehicle garage, an auto shop), the battery module 22 may simplybe re-installed back into service.

As noted above with respect to the acts represented by block 770, atleast a portion of the power assembly 84, at least a portion of theinterconnect assemblies 128, at least a portion of the side assemblies106, at least a portion of the battery control assembly 70, or anycombination thereof, may be remanufactured in accordance with presentembodiments. FIGS. 82-90 each represent general methods by whichsections of the battery module 22 may be remanufactured in accordancewith the present disclosure. It should be noted that these methods arepresented separately only to facilitate discussion. Indeed, any of theacts described hereinbelow may be used in any combination such that aremanufacturing process may incorporate some or all of the actsdescribed with respect to FIGS. 82-90.

As noted above, the particular manner by which the battery modules 22described herein are remanufactured may depend on a number of factors,including time considerations, cost considerations, the expertise of theindividual performing the remanufacture, the configuration of theautomated machinery performing the remanufacture, the desiredconfiguration of the remanufactured battery module, or any combinationthereof. Further, the automated machinery performing the remanufacturemay include suitably configured storage and processing components forperforming the methods described herein. For example, an automatedremanufacturing system may include one or more tangible,machine-readable, non-transitory media collectively storing one or moresets of instructions that are executable by one or more processingdevices, such as a processor of the automated machinery, to perform thetasks presented below. Furthermore, such automated machinery may performsome or all of the acts represented by FIG. 81, which may include actsillustrated in subsequent figures.

Discussed hereinbelow are various methods of remanufacturing certainportions of the battery module 22. Beginning with FIG. 82, the methodsare first presented in a more general context, i.e., from the standpointof remanufacturing entire sections (e.g., assemblies) of the batterymodule 22, and are followed by methods of remanufacturing particularportions of those sections. For instance, method 778 of FIG. 82 isdescribed in the context of remanufacturing the combination formed bythe top and bottom compression plates 100, 102, the power assembly 84,and the interconnect assemblies 128, and is followed by methods ofremanufacturing each of these assemblies (e.g., separate from oneanother) in FIGS. 84 and 85.

Moving now to the more particular methods of remanufacturing the batterymodule 22, because the power assembly 84 and interconnect assemblies 128include portions that will generally degrade over time, remanufacturingin accordance with one embodiment may include replacing at least onecomponent of each with a new respective component. FIG. 82 represents anembodiment of such a method 778. In particular, the method 778 includesremoving (block 780) the plastic or composite cover 59, the sideassemblies 106, the end assemblies 80, and the battery control assembly70 away from the remainder of the battery module 22. For example, theplastic or composite cover 59 and the battery control assembly 70 may beunfastened (e.g., by pulling away, by unscrewing, or a combinationthereof) from the top compression plate 100, and may be displaced awayfrom the power assembly 84, for example along the Y axis 42. Similarly,in some embodiments, the side assemblies 106 may be unfastened from thetop and bottom compression plates 100, 102 (or other portion of thebattery assembly 84), and displaced away from the power assembly 84, forexample along the X axis 44. The end assemblies 80 may be unfastenedfrom the interconnect assemblies 128, the power assembly 84, and/or thetop and bottom compression plates 100, 102, and displaced away from thepower assembly 84, for example along the Z axis 40. Each of the plasticor composite cover 59, the side assemblies 106, the end assemblies 80,and the battery control assembly 70 may independently be individuallyretained as entirely used components, be individually remanufactured soas to incorporate both new and used components, or be individuallyaltogether replaced with a new respective assembly, in accordance withcertain embodiments disclosed hereinbelow.

Once the assemblies noted above are removed, the remainder of thebattery module 22 may be the power assembly 84 connected to the top andbottom compression plates 100, 102, and also to the interconnectassemblies 128. As noted above, such a structure may be referred to as acompressed and interconnected power assembly. In accordance with presentembodiments, all or a portion of the compressed and interconnected powerassembly may be replaced or remanufactured (block 782). For example,where time of remanufacture is a concern, once the compressed andinterconnected power assembly is isolated, it may simply be replacedwith a new compressed and interconnected power assembly. Exampleembodiments of the manner in which the compressed and interconnectedpower assembly may be remanufactured are discussed in detail below.

The method 778 also includes, after the acts represented by block 782,securing (block 784) the side assemblies 106, the end assemblies 80, andthe battery control assembly 70, which may independently be entirelyused, entirely new, or remanufactured, to the remanufactured or replacedcompressed and interconnected power assembly 84. The plastic orcomposite cover 56 may then be secured (block 786) to produce theremanufactured battery module 22. In accordance with method 778, theremanufactured version of the battery module 22 may, as a result ofthese acts, include the side assemblies 106, the end assemblies 80, thebattery control assembly 70, and a remanufactured or new version of thecompressed and interconnected power assembly, where at least a portionof the power assembly 84, the interconnect assemblies 128, or acombination thereof, is new, and at least another portion of the sideassemblies 106, the end assemblies 80, the battery control assembly 70,the power assembly 84, the interconnect assemblies 128, or anycombination thereof, is used.

It should be noted that in certain embodiments, the compressed andinterconnected power assembly may not necessarily be replaced orremanufactured. Indeed, in certain embodiments, the compressed andinterconnected power assembly may be suitable for re-use in theremanufactured battery module 22. In such embodiments, other portions ofthe battery module 22 may be remanufactured. FIG. 83 is a process flowdiagram of an embodiment of a method 790 to produce such aremanufactured version of the battery module 22. However, it should benoted that any of the acts described herein with respect to FIG. 83 mayalso be performed in any combination with any of the acts describedabove with respect to FIG. 82. That is, the acts described with respectto FIG. 83 may be performed such that the compressed and interconnectedpower assembly is used, new, or remanufactured.

As depicted, the method 790 includes removing the plastic or compositecover 59, the side assemblies 106, the end assemblies 80, and thebattery control assembly 70 from the compressed and interconnected powerassembly in accordance with the acts represented by block 780 describedabove. The method 790 also includes, upon appropriate disassembly inaccordance with block 780, replacing or remanufacturing (block 792) allor a portion of the polymer or composite cover 59, the side assemblies106, the end assemblies 80, the battery control assembly 70, or anycombination thereof.

With respect to the polymer or composite cover 59, remanufacturing mayinclude replacing various screws or other features used to secure thepolymer or composite cover 59 to the battery module 22, replacingvarious removable portions (e.g., pads) where the polymer or compositecover 59 may interface with various other components (e.g., theterminals 24, 26, 30), or any other similar replacement. Alternatively,the polymer or composite cover 59 may simply be replaced with a newversion.

With respect to the side assemblies 106, remanufacturing in accordancewith block 792 may include replacing the thermal gap pads 108, the heatsink side plates 60, 62, the screws 110 (or other fastening features),or any combination thereof. The present embodiments are also intended toencompass situations where only one of the side assemblies 106 isremanufactured or replaced. Thus, the thermal gap pads 108 may,individually and independently, be new or used, the heat sink sideplates 60, 62 may, individually and independently, be new or used, andthe screws 110 (fastening features) may, independently and individually,be new or used.

With respect to the end assemblies 80, either or both may beremanufactured or replaced. For example, features of the end assemblies80 that may experience deformations or other degradation as a result ofthermal fluctuations may be replaced, including but not limited to therectangular gaskets 86, the vent discs 96, the gap pads 82, theinsulating polymer layer 90, or any combination thereof. The end plates92 may, in addition to these features or as an alternative to thesefeatures, be replaced.

A variety of operations may be performed so as to generate aremanufactured version of the battery control assembly 70. Furthermore,in some embodiments, the entire battery control assembly 70 may bereplaced with a new respective version (not necessarily having the exactsame configuration). By way of non-limiting example, any one or acombination of the electrical features of the battery control assembly70 may be replaced or re-plated (e.g., with a new or fresh metalliccoat), including but not limited to the connections 58, the conductiveportions of the cables 74 (and even the cables 74 themselves),interconnects between the cables 74 and the interconnect assemblies 128,or any combination thereof. In addition to replacing or re-plating thesefeatures, the DC-DC converter 76 may be removed and replaced (or notreplaced, depending on a desired configuration of the remanufacturedversion of the battery module 22).

The battery control module 72 may undergo re-soldering of variouselectrical connections to new or used interfaces, may be re-programmed,or altogether replaced. In embodiments where the battery control module72 is replaced or reprogrammed, the new or reprogrammed version of thebattery control module 72 may not necessarily have the same programmingas the used version. For example, the new or reprogrammed version of thebattery control module 72 may have a programming more appropriatelysuited to the remanufactured version of the battery module 22, which mayhave different desired operating temperatures, operating voltages, orthe like, compared to the used version of the battery module 22. Indeed,in certain embodiments, the new or reprogrammed version of the batterycontrol module 72 may have a programming more appropriately suited to adifferent use or use within a different climate (e.g., use within asport utility vehicle versus a compact car, or use in a cold climateversus a warm climate).

Once the plastic or composite cover 59, the side assemblies 106, the endassemblies 80, the battery control assembly 70, or any combinationthereof, have been suitably remanufactured, the method 790 thenprogresses to securing (block 794) these components back to thecompressed and interconnected power assembly. For example, while theside assemblies 106, the end assemblies 80, and the battery controlassembly 70 may be secured to the compressed and interconnected powerassembly in any order, in some embodiments, the side assemblies 106 mayfirst be secured to the compressed and interconnected power assembly.Indeed, because, as noted above, the side assemblies 106 may function asheat sinks with respect to the compressed and interconnected powerassembly, it may be desirable to ensure intimate contact therebetween.By way of non-limiting example, the battery control assembly 70 may besecured to the top compression plate 100 and to both side assemblies106. The end assemblies 80 may each be connected to both side assemblies106, the top and/or bottom compression plates 100, 102, one of theinterconnect assemblies 128, or any combination thereof.

The plastic or composite cover 56 may then be secured (block 796) toproduce a remanufactured version of the battery module 22. In accordancewith method 790, the remanufactured version of the battery module 22may, as a result of these acts, include new, used, or remanufacturedversions, or any combination thereof, of the side assemblies 106, theend assemblies 80, the battery control assembly 70, and aremanufactured, new, or entirely used version of the compressed andinterconnected power assembly.

The power assembly 84 may be compressed by the top and bottomcompression plates 100, 102 to achieve, using the plurality of layers ofeach battery cell assembly 114, a certain amount of pressure on eachbattery cell 116, and the interconnect assemblies 128 may be used tointerconnect two or more of the battery cells 116. In certainsituations, the top and bottom compression plates 100, 102 and theinterconnect assemblies 128 may be sufficiently re-usable such that theymay be retained, and all or a portion of the power assembly 84 (e.g., atleast one layer of the plurality of layers of at least one of thebattery cell assemblies 114) may be replaced. FIG. 84 is a process flowdiagram illustrating an embodiment of such a method 800. As may beappreciated, the method 800 may be performed in conjunction with any ofthe methods described above with respect to FIGS. 82 and 83. Forinstance, in some embodiments, the method 800 may constitute some or allof the acts represented by block 782 in FIG. 82.

As illustrated in FIG. 84, the method 800 includes removing (block 802)the interconnect assemblies 128 from the power assembly 84, such as byremoving the screws 136 that secure the interconnect assemblies 128 tothe top and bottom compression plates 100, 102 and, by extension, thepower assembly 84. As discussed above, the interconnect assemblies 128provide at least some structural support for the power assembly 84, suchas by indirectly supporting the power assembly 84 through the top andbottom compression plates 100, 102. In one embodiment, upon removing theinterconnect assemblies 128 from the power assembly 84, such as alongthe Z axis 40, the top and bottom compression plates 100, 102 may thenbe removed. For example, the compression bolts 140 may be loosened andremoved, and the top and bottom compression plates 100, 102 may beseparated from the remainder of the power assembly 84 (e.g., along the Yaxis 42).

Once the power assembly 84 is isolated, the power assembly 84 may bereplaced or remanufactured (block 804). For example, where time is aconcern and in situations where it may be desirable to replace all ofthe battery cells 116 and/or other layers of the battery cell assemblies114, the entire power assembly 84 may be replaced with a new respectivepower assembly 84. As noted above, the power assembly 84 may notnecessarily have the same configuration as the used power assembly 84.For example, the new power assembly 84 may be rated to operate within adifferent temperature range, to provide electrical energy at a differentcurrent and/or voltage, or any combination of these and otherconfiguration changes. This may be accomplished using different phasechange materials within the phase change material layers 124, by usingnew gap pads 115 having a different thermal conductivity than the usedgap pads 115, by using different battery cells 116, or any combinationof these and other material/layer modifications. FIGS. 86 and 87,discussed in detail below, depict example methods by which individualportions of the power assembly 84 may be replaced to remanufacture thepower assembly 84.

Once the power assembly 84 is appropriately replaced or remanufacturedaccording to the acts represented by block 804, the interconnectassemblies 128 and the top and bottom compression plates 100, 102 may besecured (block 806) to the power assembly 84 to produce a remanufacturedversion of the battery module 22. In certain embodiments, one or more ofthe fastening mechanisms (e.g., screws, clamps, clips, snap-fits) usedto secure the interconnect assemblies 128 and/or the top and bottomcompression plates 100, 102 may be replaced at this stage.

As noted above, in addition to or in lieu of remanufacturing the powerassembly 84, either or both of the interconnect assemblies 128 and/orthe top and/or bottom compression plates 100, 102 may be remanufactured.FIG. 85 is a process flow diagram depicting an embodiment of such amethod 810. In particular, the method 810 may be performed inconjunction with any of the methods introduced above, or may beperformed as an entirely separate process.

As depicted, the method 810 includes some of the same acts as describedabove with respect to the method 800 in FIG. 84. Specifically, the actsrepresented by block 802, i.e., removing the interconnect assemblies 128and the top and bottom compression plates 100, 102, may be performed soas to at least partially isolate each assembly from the other in amanner that facilitates remanufacture.

The method 810 further includes replacing or remanufacturing (block 812)either or both of the interconnect assemblies 128 and/or either or bothof the top and bottom compression plates 100, 102. By way of example,either or both of the interconnect assemblies 128 and/or either or bothof the top and bottom compression plates 100, 102 may simply be replacedwith a new respective assembly or compression plate.

While more involved processes of remanufacturing the interconnectassemblies 128 are discussed in detail below with respect to FIGS. 88and 89, in a general sense, the interconnect assemblies 128 may beremanufactured by replacing one or more of the sensors 132 with a newrespective sensor, replacing one or more of the interconnect devices 138with a new respective interconnect device (which may be the same ordifferent as the used interconnect devices 138) replacing the cellinterconnect board 130, re-plating the various metallic interconnectsand/or conductors, or any combination thereof.

With respect to the top and bottom compression plates 100, 102, thelocked nut features 142 may be replaced or otherwise repaired using newmaterial. The compression bolts 140, while not integral with the top andbottom compression plates 100, 120, may also be replaced or otherwisere-plated or repaired to ensure that an appropriate amount of pressureis provided to the power assembly 84. Indeed, the compression bolts 140(or other mechanism used to facilitate the pressurization of the powerassembly 84) may be replaced at this stage or, as noted above withrespect to FIG. 84, at a subsequent stage when the remanufacturedversion of the compressed and interconnected assembly is produced. As anexample, the compression bolts 140 may be replaced with compressionbolts 140 having different torque limits.

Once either or both of the interconnect assemblies 128 and/or either orboth of the top and bottom compression plates 100, 102 areremanufactured or replaced according to the acts represented by block812, the method 810 may include securing (block 814) the remanufacturedor replaced assemblies 128 and/or top and/or bottom compression plates100, 102 to the power assembly 84. The acts of block 814 may generallybe the same as those described above with respect to block 806 in FIG.84, although the manner in which the securing is performed may bedifferent depending on whether the fastening mechanisms have beenreplaced with a different type of mechanism. By way of non-limitingexample, a clamp may be replaced with a screw, or vice-versa.

As set forth above with respect to FIG. 84, FIGS. 86 and 87 each depictmore specific methods for remanufacturing the power assembly 84, wherethe entire power assembly 84 is not replaced but rather, one or moreportions of the power assembly 84 are replaced. In particular, FIG. 86depicts a method 820 of remanufacturing the power assembly 84 byreplacing or remanufacturing one or more of the battery cell assemblies114. Thus, a remanufactured version of the battery module 22 produced inaccordance with the method 820 will include at least a remanufacturedpower assembly 84 where at least a portion of at least one battery cellassembly 114 is new.

Specifically, the method 820 includes separating (block 822) the powerassembly 84 into one or more individual battery cell assemblies 114. Theacts represented by block 822 may include, by way of non-limitingexample, de-registering each battery cell assembly 114 from every otherbattery cell assembly 114 by, for example, separating the frames 118 ofthe battery cell assemblies 114. In embodiments where the registrationfeatures 121 include various retention features, such as clamps orlocks, the retention features may be removed, loosened, or even, incertain embodiments, broken.

Once the battery cell assemblies are appropriately separated inaccordance with the acts represented by block 822, one or more of thebattery cell assemblies 114 may be replaced with a new respectivebattery cell assembly 114, or may be remanufactured (block 824). By wayof non-limiting example, the one or more battery cell assemblies 114 maybe replaced with new respective battery cell assemblies 114 havinggenerally the same configuration (e.g., the same number of layers,arrangement and order of layers, type of layers) or having a differentconfiguration (e.g., a different number of layers, arrangement and orderof layers, or type of layers). Indeed, in certain embodiments, such aswhen the battery cell assemblies 114 are replaced with new battery cellassemblies 114 having a different configuration, the differentconfiguration may enable the remanufactured version of the batterymodule 22 to be used in a different type of climate (e.g., by having adifferent appropriate operating temperature range), to be used forproviding electrical energy at different currents and/or voltagescompared to the used version of the power assembly 84, to provideenhanced water resistance (e.g., as in a marine battery), to provideenhanced vibration dampening, or any combination thereof.

While replacing individual battery cell assemblies 114 may be desirablein some circumstances, in other situations, it may be desirable toremanufacture individual battery cell assemblies 114 by replacing aportion (e.g., a layer, a portion of a layer) of at least one batterycell assembly 114 with a new respective portion. Such embodiments aredescribed in further detail below with respect to FIG. 87.

Once the one or more battery cell assemblies 114 are appropriatelyreplaced in accordance with the acts represented by block 824, thebattery cell assemblies 114 (including both used and new battery cellassemblies 114) may be re-registered (block 826) to one another to formthe remanufactured version of the power assembly 84. For example, theregistration features 121 of the battery cell assemblies 114 may bealigned and appropriately coupled (e.g., via male/female connection,clamps, screws, interference fit) so as to ensure proper alignment ofthe battery cell assemblies 114 and enable appropriate connection to theinterconnect assemblies 128.

In addition to, or as an alternative to, replacing one or more batterycell assemblies 114, one or more individual layers of certain batterycell assemblies 114 may be replaced, as set forth in FIG. 87. Inparticular, FIG. 87 depicts a method 830 of remanufacturing individualbattery cell assemblies 114 by replacing at least a portion of at leastone layer of the plurality of layers forming the battery cell assembly114. Thus, the method 830 may be performed as an alternative to, or incombination with, any of the methods set forth above with respect toFIGS. 81-86.

As depicted, the method 830 includes separating (block 832) at least onebattery cell assembly 114 into its constituent layers, which may includeany one or a combination of the layers discussed above in anyembodiment. By way of example, referring to the embodiment of thebattery module 22 depicted in FIG. 7, the constituent layers mayinclude, but are not limited to, the gap pad 115, the internal heat fin112, the phase change material layer 124, the frame 118, the batterycell 116, or any combination thereof. The separation may be performed,in some embodiments, simply by pulling layers away from one another(e.g., generally along the Y axis 42). In other embodiments, the layersmay be secured to one another using, for example, chemical and/ormechanical fastening methods (e.g., an adhesive, clamp, clip, bolt,hook-and-loop connector). In such embodiments, the layers may beseparated using appropriate processes associated with the particularfastening method. For instance, the adhesive coupling may be undoneusing a solvent, heat, a cutting tool (e.g., a razor), or anycombination thereof.

Once separated, one or more layers of the battery cell assembly 114, orportions of one or more of the layers, may be replaced with a newrespective layer or portion (block 834). The particular layers of thebattery cell assemblies 114 that are replaced may depend on, by way ofnon-limiting example, the testing and inspection performed in accordancewith the acts represented by block 764 of FIG. 81. For example, inembodiments where the power assembly 84 is not producing a desiredcurrent and/or voltage of electrical energy, one or more of the batterycells 116 may be replaced with a new respective battery cell 116. In yetother embodiments, the testing may indicate that the power assembly 84is not producing the desired electrical energy, but may also indicatethat the battery cells 116 are each producing a desired amount ofelectrical energy. In such embodiments, other layers that couldpotentially affect the operation of the power assembly 84 may bereplaced, including but not limited to the gap pads 115 and/or otherlayers that affect the pressure exerted on each battery cell 116.Additionally or alternatively, the testing may indicate that the powerassembly 84 or, one of the battery cell assemblies 114 in particular, isoperating outside of a desired temperature range. In such situations,the phase change material layer 124 may be replaced, or may be infusedwith additional (new) phase change material. The gap pads 115 may,additionally or alternatively, be replaced for temperature reasons.

Additionally or alternatively, the battery cells 116 may be replaced tore-purpose the battery module 22. For example, the new battery cells 116may have different voltage and/or current ratings compared to their usedcounterparts. That is, the used battery cells 116 may be rated, based onwhen they were originally manufactured, at a first voltage or current,and the new battery cells 116 may be rated at a second voltage orcurrent, where the first voltage or current and the second voltage orcurrent are different.

In still further embodiments, certain of the layers of the battery cellassemblies 114 may be replaced due to wear. For example, in embodimentswhere the battery module 22 is positioned within a vehicle, the batterymodule 22 may experience not only thermal fluctuations due to normaloperation and climate, but may also be subjected to a variety of otherenvironmental conditions that can degrade various components over time,such as humid air, salty air, road vibrations, debris, and the like.Accordingly, certain layers of the battery cell assemblies 114 may becrazed, broken, bent, oxidized, stained, or otherwise unsuitable for usewithin a remanufactured version of the battery module 22. In embodimentswhere worn layers are present in this manner, they may be replaced.

Once the one or more layers of the battery cell assemblies 114 arereplaced, the layers of each battery cell assembly may be registered(block 836) to one another to produce at least one remanufacturedversion of the battery cell assembly 114. The acts represented by block836 may include, by way of example, stacking the layers against oneanother in a particular order. As discussed above, it may be desirableto stack the layers of the battery cell assemblies 114 in a particularorder (e.g., the order shown in FIG. 7) to obtain desired amounts ofthermal conduction and to enable the provision of appropriate amounts ofpressure on the battery cells 116. Indeed, either or both of theseparameters may be important for ensuring homogenous operation betweenall of the battery cell assemblies 114 (e.g., substantially equalvoltage and/or current output).

In other embodiments, the acts associated with block 836 may includesecuring the layers to one another, for example using an adhesive,hook-and-loop fastener, clamp, clip, soldering, crimping, bolting,screwing, friction fits, or any other features or methods suitable forsecuring one layer to another. Once the layers are secured to oneanother, the resulting battery cell assembly 114 may be a remanufacturedbattery cell assembly having at least one layer (of a plurality oflayers) being new or having a new portion, and having at least one otherlayer (of the plurality of layers) being used. The resultingremanufactured battery cell assembly 114 may be incorporated into aremanufactured version of the power assembly 84, which may in turn beincorporated into a remanufactured version of the battery module 22.Thus, the remanufacturing processes associated with FIG. 87 may be usedin conjunction with any one or a combination of the other methods setforth above.

As generally noted above with respect to FIGS. 81 and 85, one or more ofthe interconnect assemblies 128 may be remanufactured, either incombination with remanufacturing other portions of the battery module22, or separate from other portions of the battery module 22. FIG. 88depicts a method 840 for remanufacturing the interconnect assemblies 128as a result of inspection and/or testing. The method 840 may beperformed as a standalone method or in combination with any of the othermethods set forth above.

As depicted, the method 840 includes inspecting and/or testing (block842) the used interconnect assembly 128. The inspecting and/or testingmay include a visual inspection of both structural support components ofthe interconnect assembly 128 (e.g., a dielectric material forming thecell interconnect board 130), as well as the electrical components ofthe interconnect assembly 128 (e.g., the sensors 132, couplingstructures 524), which, in certain embodiments, may include one or moreportions of at least one of the terminals 24, 26, 30. The inspectionand/or testing may be performed in a similar manner as set forth abovewith respect to FIG. 81, such as by performing electrical measurementson the conductive portions of the interconnect assembly 128 and/or byvisually inspecting the conductive portions for abrasion, pitting,scratching, metallic oxidation (i.e., corrosion), debris buildup, welddecay, and the like.

Assuming that the interconnect assembly 128 is eligible forremanufacturing, the interconnect assembly 128 may be remanufacturedaccording to the results of the testing and/or inspection (block 844).By way of non-limiting example, the acts associated with block 844 mayinclude reinforcing structural portions of the interconnect assembly 128if the structural portions exhibit wear evidenced by cracking, crazing,chipping, or the like. In other embodiments, the structural portions(e.g., the dielectric of the cell interconnect board 130) may simply bereplaced if the structural portions are not repairable or otherwisesuitable for use in a remanufactured implementation of the batterymodule 22.

The acts associated with block 844 may, additionally or alternatively,include re-plating, re-coating, filing, re-soldering, or similarlyprocessing the conductive portions of the interconnect assembly 128(e.g., the coupling structures 524, the sensors 132). For example, avisual inspection of the interconnect assembly 128 may indicate thatvarious electrical connections between conductive portions of theinterconnect assembly 128 may be loose, worn, or broken. In suchsituations, a new or reinforced connection may be established byre-soldering. In still further embodiments, as another example,electrical tests may reveal that certain conductive portions of theinterconnect assembly 128 no longer have a suitable conductivity. Insuch situations, those conductive portions may be re-coated, re-plated,or altogether replaced. Once the interconnect assembly 128 isremanufactured in accordance with block 844, the remanufactured versionof the interconnect assembly 128 may be inspected and/or tested (block846) to ensure compliance with an appropriate standard, and to ensurethat any negative results of testing before the remanufacturing processhave been appropriately corrected.

The methods set forth above relate to the general manner by whichvarious portions of the battery module 22 may individually beremanufactured. Again, the methods discussed above may be performed asstandalone methods, or in any combination. Indeed, the presentdisclosure is also intended to encompass certain remanufacturing methodsthat may involve remanufacturing combinations of assemblies to achieve aparticular result. For instance, as discussed above with respect to FIG.81, the electrical components of the battery module 22 may beremanufactured or replaced. As discussed in detail below with respect toFIG. 89, the battery module 22 may be remanufactured to achieve adifferent operating temperature range, or simply to replenish thecapability of the battery module 22 to dissipate heat.

In particular, FIG. 89 illustrates an embodiment of a method 850 toremanufacture the battery module 22 by replacing all or a portion of thelayers that have an effect on the thermal capabilities of the batterymodule 22. As depicted, the method 850 includes removing (block 852) thepolymer or composite cover 59, the side assemblies 106, the endassemblies 80, the battery control assembly 70, the interconnectassemblies 128, and the top and bottom compression plates 100, 102 toisolate the power assembly 84. It should be noted that the actsrepresented by block 852 may be a combination of the acts describedabove with respect to block 780 of FIG. 82 and block 802 of FIG. 84.

The power assembly 84 may then be separated (block 822) into individualbattery cell assemblies 114 in the manner set forth with respect to FIG.86 above. Following the separation in accordance with block 822, theindividual battery cell assemblies 114 may then be separated (block 832)into individual layers in the manner set forth with respect to FIG. 87above.

Once the layers of the battery cell assemblies 114 have been separated,at least a portion of one or more of the thermal control layers of thebattery cell assemblies 114 may be replaced (block 853). Generally, atleast a portion of one or more of the gap pads 115, phase changematerial layers 124, and/or internal heat fins 112 of the power assembly84 may be replaced. In still further embodiments, the phase changematerial layers 124 may be remanufactured by providing additional phasechange material to the layers 124. The internal heat fins 112 may bere-shaped, re-plated, cut, or otherwise processed to enable enhancedheat transfer to the side assemblies 106 upon re-assembly of the batterymodule 22.

At least a portion of the side assemblies 106 may be replaced (block854), as well. For example, the heat sink side plates 60, 62, thethermal gap pads 108, or a combination thereof, may be replaced.

It should be noted that the new respective layers (e.g., new phasechange material layers 124, new gap pads 115, new thermal gap pads 108,new internal heat fins 112, or any combination thereof) may have thesame configuration as their used counterparts, or may have differentproperties. For example, the new respective layers may enable operationof the battery module 22 at higher temperatures, or at lowertemperatures when compared to the battery module 22 having the usedrespective layers. In certain embodiments, using new thermal layers(e.g., new phase change material layers 124, new gap pads 115, newthermal gap pads 108, new internal heat fins 112, or any combinationthereof) may enable a wider temperature range than those employed in theused battery module 22. Indeed, the particular type of layer selectedfor each location may have an impact on the overall thermal managementof the battery module 22. Furthermore, replacing the heat sink sideplates 60, 62 with new respective plates 60, 62 may also have an effecton the thermal management of the battery module 22, for exampledepending on the size, shape, and extent of the external heat fins ofthe new heat sink side plates 60, 62 versus the used heat sink sideplates 60, 62. Once the components that effect the thermal management ofthe battery module 22 have been suitably replaced or remanufactured, thecomponents of the battery module 22 may then be re-assembled (block 856)to generate the remanufactured version of the battery module 22.

As set forth above, the remanufacturing processes described herein arenot limited to producing the same battery module 22 obtained beforeremanufacture. In other words, in certain embodiments, theremanufacturing may result in re-purposing of the battery module 22. Asan example of re-purposing the battery module 22, the battery module 22may be re-purposed to provide electrical energy at different voltagesand/or currents, which may enable its use in an entirely differentimplementation (e.g., a boat or house versus a vehicle). Among otherapproaches, including changing the voltage and/or current ratings of theindividual battery cells 116 as discussed above, one approach ispresented in FIG. 90, which depicts a method 860 for repurposing of thebattery module 22 by re-arranging the manner in which the battery cells116 are connected using the interconnect assembly 128. It should benoted that the method 860 may be used in conjunction with other methodsdescribed above.

The method 860 depicted in FIG. 90 provides various processes that maybe used to remanufacture the interconnect assembly 128 to re-configurethe battery module 22 to provide a different electrical output, such asa different voltage, a different current, or both. As illustrated, themethod 860 includes removing (block 862) the interconnect assemblies 128from the power assembly 84. It should be noted that the acts representedby block 862 may be substantially the same as set forth above withrespect to block 802 of FIG. 84. In a general sense, the acts of block862 may result in isolating the interconnect assemblies 128 from thebattery cells 116.

The method 860 may also include, as illustrated, providing (block 864) anew conductor, or additional conductive materials, to electricallycouple groupings of the coupling structures 524 (e.g., on the cellinterconnect board 130) in parallel. For example, certain of thecoupling structures 524 that would otherwise be electrically isolatedmay be connected to the negative terminal 24 (or interface for thenegative terminal 24) or the second positive terminal 30 in a parallelarrangement.

Additionally, the method 860 may include remanufacturing, replacing, orreusing the power assembly 84 (block 866), depending on the particularend use of the remanufactured battery module 22 and the suitability ofthe power assembly 84 for that particular end use. In embodiments wherethe power assembly is remanufactured, the acts represented by block 866may be the same as set forth above with respect to block 804 of FIG. 84and may include at least some of the acts set forth above with respectto method 820 of FIG. 86 and/or method 830 of FIG. 87.

The method 860, as illustrated, also includes connecting (block 868)sets of serially-arranged battery cells 116 in parallel. For example,sets of battery cells 116 may be connected serially. However, ratherthan connecting all of the battery cells 116 in series, more than twobattery cells 116 may not be connected at one end to another batterycell 116, but instead are connected to a terminal (e.g., the negativeterminal 24 or one of the positive terminals 26, 30) in a parallelarrangement with at least one other set. The arrangement resulting fromthis connection scheme may be further appreciated with respect to FIG.91, which is a side-view schematic illustration of sets 880 of thebattery cells 116 being interconnected serially to form the sets 880,and the sets 880 being connected in parallel to a respective terminal.It should be noted that FIG. 91 is merely a schematic representation ofan embodiment of one connection scheme to achieve different connectivityscheme than those embodiments described above.

As illustrated in FIG. 91, the repurposed battery module 22 includes thesets 880 of the battery cells 116, which may, in an actualimplementation, be positioned within battery cell assemblies 114 and,thus, the power assembly 84. The sets 880 include a first set 882, asecond set 884, and a third set 886, each set 880 having three batterycells 116 connected in series. However, as represented between thesecond and third sets 884, 886, any number of sets 880 may be used toachieve a desired output voltage.

With reference to the first set 882 as an example, each set 880, asillustrated, includes a first battery cell 888, with a negative tabelectrode 890 being connected to one of the coupling structures 524without being interconnected with another battery cell 116 at a negativeend 892. Instead, the negative end 892 of the first battery cell 88 isconnected, via the coupling structure 524 (or, in some embodiments,directly coupled) to the negative terminal 24. As shown, the respectivefirst battery cells 888 of the second and third sets 884, 886 are alsoconnected to the negative terminal 24 in this manner. While the first,second, and third sets 882, 884, 886 may be separately connected to thenegative terminal 24 (or negative terminal interface), as illustrated,they are coupled in parallel via a negative bus 894 to the negativeterminal 24.

A similar arrangement may be present with respect to the positiveterminals 26, 30. For example, with reference to the first set 882, thefirst battery cell 888 is also connected, in a series arrangement, tosecond and third battery cells 896, 898. While the second battery cell896 is serially connected at both ends to another battery cell (e.g.,via the coupling structures 524 and tab electrodes 129), the thirdbattery cell 898 is not. Rather, a positive end 900 of the third batterycell 898 is connected via a positive tab electrode 902 to the firstand/or second positive terminals 26, 30 (e.g., via one of the couplingstructures 524). This arrangement is similar for each set 880.

The respective third battery cells 898 of the second and third sets 884,886 are also similarly connected to the first and/or second positiveterminals 26, 30. Indeed, the third battery cells 898 may be separatelyconnected to the first and/or second positive terminals 26, 30 or, asillustrated, may be connected in parallel via a positive bus 904 to thefirst and/or second positive terminals 26, 30. The negative and positivebuses 894, 904 may be formed by extensions from an already-existing bus(e.g., the negative bus bar 104), or may be disposed on the cellinterconnect board 130 of the interconnect assemblies 128 as newconductors. In particular, the buses 894, 904, and their connections tothe first, second, and third sets 882, 884, 886 of battery cells 116,may be formed according to the acts represented by block 864 of FIG. 90.

It should be appreciated that the configuration depicted in FIG. 91results in a lower output voltage than other embodiments describedabove, for example with respect to FIG. 40. However, the voltage output,while lower, may have a higher associated current due to the parallelconnections of the sets 882, 884, 886. Accordingly, one implementationof the repurposed version of the battery module 22 set forth in FIG. 91may be one in which the voltage desired is slightly lower (e.g., 12V,which may be obtained when each battery cell outputs 4V) but the currentdesired is higher. It should be noted that the reconfigurationrepresented by FIG. 77 is provided as an example. Differentreconfigurations may be performed in accordance with presentembodiments. For example, the battery cells 116 may be changed frombeing in series to being in parallel in any variation.

One or more of the disclosed embodiments, alone or on combination, mayprovide one or more technical effects useful in the remanufacture ofbattery modules, and portions of battery modules. For example, certainembodiments of the present approach may enable extended lifetimes ofvarious portions of the battery module 22, including the battery cells116, heat sink side plates 60, interconnect assemblies 128, batterycontrol modules 72, and other materials that can be difficult torecycle. Indeed, the approaches described herein may improve theperformance of battery modules 22 by enabling the selective replacementof individual components, and may ultimately reduce the time requiredfor a technician to service a vehicle (or other location) having thebattery module 22. By specific example, replacing a used component ofthe battery module 22 with a new respective component may enable theresulting remanufactured battery module 22 to approach its originalperformance standards. The technical effects and technical problems inthe specification are exemplary and are not limiting. It should be notedthat the embodiments described in the specification may have othertechnical effects and can solve other technical problems.

While only certain features and embodiments of the invention have beenillustrated and described, many modifications and changes may occur tothose skilled in the art (e.g., variations in sizes, dimensions,structures, shapes and proportions of the various elements, values ofparameters (e.g., temperatures, pressures, etc.), mounting arrangements,use of materials, colors, orientations, etc.) without materiallydeparting from the novel teachings and advantages of the subject matterrecited in the claims. The order or sequence of any process or methodsteps may be varied or re-sequenced according to alternativeembodiments. It is, therefore, to be understood that the appended claimsare intended to cover all such modifications and changes as fall withinthe true spirit of the invention. Furthermore, in an effort to provide aconcise description of the exemplary embodiments, all features of anactual implementation may not have been described (i.e., those unrelatedto the presently contemplated best mode of carrying out the invention,or those unrelated to enabling the claimed invention). It should beappreciated that in the development of any such actual implementation,as in any engineering or design project, numerous implementationspecific decisions may be made. Such a development effort might becomplex and time consuming, but would nevertheless be a routineundertaking of design, fabrication, and manufacture for those ofordinary skill having the benefit of this disclosure, without undueexperimentation.

The invention claimed is:
 1. A system, comprising: a battery module; a battery cell assembly that is a component of the battery module; a battery cell of the battery cell assembly, wherein the battery cell comprises a first planar surface and generates heat during operation; and a phase change material (PCM) layer that is substantially planar and is stacked against the first planar surface of the battery cell, wherein the PCM layer includes a plurality of graphite layers that is oriented to predominantly conduct the heat across the thickness of the PCM layer, and wherein the PCM layer absorbs a portion of the heat to affect a phase change in a phase change in a phase change element disposed around the plurality of graphite layers.
 2. The system of claim 1, wherein the battery cell is a pouch battery cell.
 3. The system of claim 1, wherein the battery module comprises an internal heat fin that is stacked against the PCM layer opposite the battery cell, and wherein the plurality of graphite layers of the PCM layer is oriented to predominantly conduct the first portion of the heat across the thickness of the PCM layer and toward the internal heat fin.
 4. The system of claim 3, wherein the battery module comprises a first heat sink side plate and a second heat sink side plate disposed on opposite sides of the battery module, wherein the internal heat fin is in thermal communication with the first heat sink side plate and the second heat sink side plate.
 5. The system of claim 4, wherein the plurality of graphite layers of the PCM layer is oriented to secondarily conduct the heat toward the first and second heat sink side plates.
 6. The system of claim 1, wherein the battery cell and the PCM layer are arranged in a horizontally stacked orientation within the battery module.
 7. The system of claim 6, wherein the PCM layer conducts the heat generated by the battery cell during operation predominantly in a vertical direction relative to the horizontally stacked orientation.
 8. The system of claim 1, wherein the PCM layer comprises a substantially planar first packaging layer and a substantially planar second packaging layer disposed on opposite sides of the plurality of graphite layers and the phase change element.
 9. The system of claim 8, wherein the substantially planar first packaging layer and the substantially planar second packaging layer comprise a first polyvinylchloride (PVC) layer and a second PVC layer.
 10. The system of claim 8, wherein the phase change element comprises a paraffin phase change element.
 11. The system of claim 8, wherein the plurality of graphite layers is oriented perpendicular to the substantially planar first packaging layer and the substantially planar second packaging layer such that heat transfer is facilitated through the PCM layer in a direction perpendicular to the substantially planar first packaging layer and the substantially planar second packaging layer.
 12. The system of claim 1, wherein the battery module comprises a plurality of battery cell assemblies.
 13. The system of claim 1, wherein the battery cell and the PCM layer are arranged in a vertically stacked orientation within the battery module.
 14. The system of claim 1, wherein the plurality of graphite layers comprise highly oriented pyrolytic graphite (HOPG), graphite, graphene, or a combination thereof.
 15. A battery module, comprising: a battery cell assembly, comprising: a pouch battery cell that is substantially planar and that generates heat during operation; a thermal gap pad that is substantially planar and is disposed adjacent to the pouch battery cell; a phase change material (PCM) layer that is substantially planar and is disposed adjacent to the thermal gap pad; and an internal heat fin having a planar portion disposed adjacent to the PCM layer, wherein the PCM layer comprises a plurality of graphite layers that is impregnated with one or more phase change components, and wherein the plurality of graphite layers is aligned with a first axis that is perpendicular to the PCM layer, and wherein the plurality of graphite layers receives the heat from the battery cell via the thermal gap pad and predominantly conducts the heat toward the internal heat fin along the first axis, and wherein the one or more phase change components absorb a portion of the heat to drive a phase change of the one or more phase change components.
 16. The battery module of claim 15, wherein the battery module comprises at least one heat sink side plate, and wherein the plurality of graphite layers is further aligned with a second axis that is perpendicular to the first axis and that is directed toward the at least one heat sink side plate of the battery module, and wherein the plurality of planar graphite layers secondarily conducts the heat towards the at least one heat sink side plate of the battery module along the second axis.
 17. The battery module of claim 15, wherein the PCM layer has a thickness less than or equal to approximately 2 millimeters.
 18. The battery module of claim 15, wherein the one or more phase change components are configured to undergo a solid to liquid phase change at a melting point temperature such that the one or more phase change components generally maintain an operating temperature of the battery module near the melting point temperature until the phase change is complete.
 19. The battery module of claim 15, wherein the thermal gap pad is substantially thermally conductive and substantially electrically non-conductive.
 20. The battery module of claim 15, wherein the thermal gap pad comprises a silicone elastomer.
 21. The battery module of claim 20, wherein the silicone elastomer is impregnated with fiber glass.
 22. A phase change material (PCM) layer, comprising: a phase change material (PCM) disposed within a packaging, wherein the PCM layer is substantially planar, and wherein the PCM layer comprises a plurality of graphite layers that is aligned along a first axis that is perpendicular to the PCM layer and that predominantly conduct heat across the thickness of the PCM layer over a first temperature range, and wherein the PCM layer comprises one or more phase change elements disposed with the plurality of graphite layers, wherein the one or more phase change elements absorb heat over a second temperature range.
 23. The PCM layer of claim 22, wherein the first temperature range is below or above a melting point temperature of the one or more phase change elements of the PCM layer.
 24. The PCM layer of claim 23, wherein the second temperature range is the melting point temperature of the one or more phase change elements of the PCM layer.
 25. The PCM layer of claim 22, wherein the packaging comprises one or more polymer packaging layers.
 26. The PCM layer of claim 22, wherein the plurality of graphite layers is further aligned along a second axis that extends along a width of the PCM layer and is perpendicular to a length of the PCM layer, wherein the plurality of graphite layers secondarily conducts heat across the width of the PCM layer. 